Ace Analysis: Stroman and Corbin

AceAnalysis Logo1The goal of the Ace Analysis Series is to analyze pitchers whose most recent performance has not met expectations, and try to determine whether the results are due to skill change, or simply a run of good/bad luck. I do take requests, so if there is a specific player you would like me to take a look at, please let me know in the comment section.

This week, our focus will shift to a couple of pitchers who have really been struggling over the past few weeks. It is always difficult to make the right call in these instances. Patience is often rewarded in fantasy baseball, but so is knowing when to cash in on a player’s name value. Marcus Stroman and Patrick Corbin are two pitchers who have underperformed fantasy owners’ expectations. Let’s take a closer look.

Marcus Stroman, Toronto Blue Jays

85.2 5 57 4.94 1.35

Marcus Stroman gained elite prospect status while racking up Ks as he cruised through the minors. He was one of fantasy baseball’s most coveted breakout pitchers before tearing his ACL during spring training last year. His stuff has been compared to Roy Halladay. After a couple successful major league stints, expectations for the 25-year-old ace were again pretty high entering the 2016 draft season. After starting the season pretty well, he has really gone in the tank over the past 30 days (7.58 ERA, 1.85 WHIP). Let’s take a look and see what is going on.

The Arsenal

According to most scouts, Stroman’s best pitch is his sinker, which he throws about half the time. He generates an elite ground ball rate on the pitch (66.7% career) and hitters tend to have a difficult time squaring it up. Opposing batters have been more successful against the sinker this season than they have the past two years (.344 wOBA in ‘16, .291 career wOBA). The downside to the sinker is that Stroman generates very few swings and misses (4.9% swinging strike rate). He relies on weak contact to get batters out.

Stroman’s off speed pitches can be very difficult to classify because his slider and curveball tend to have similar breaking action. For that reason, I will not get in too much detail with usage percentages. Instead, I will briefly touch on each of his four off speed pitches which are a large part of Stroman’s pitch mix.

Stroman uses his cutter to try and keep hitters off-balance when they are looking for the sinker. It is a decent pitch, but he does not get a ton of swings and misses with it,and it is his only pitch that does not yield a high ground ball rate. This year, opposing hitters have really mashed the cutter. Four of Stroman’s seven home runs allowed have come on this pitch. That is probably a fluke since he gave up zero home runs on cutters during his two previous major league stints, but it is something to keep an eye on.

Stroman’s best two breaking pitches are his slider and curveball. He is able to generate high swinging K rates on each pitch, and they also offer high ground ball rates. Both pitches have a lot of vertical drop. In fact, Stroman’s slider actually drops as much or more than his curveball. This season, opposing hitters have a wOBAs of .235 against the curve and .171 against the slider.

Stroman’s final breaking pitch is his changeup. He is also able to get a high ground ball rate and an above average swinging strikeout rate on the change, but he has struggling with hard contact. His career wOBA is .374 on the changeup, easily the highest of any of his offerings.

Ks and BBs

Stroman’s off speed pitches have really good swinging strike rates. The problem is that his two most frequently used offerings do not. For that reason, his 15.7% strikeout rate should not be too surprising for fantasy owners. Stroman’s 8.2% overall swinging strike rate is well below league average. As long as his sinker and cutter account for nearly 70% of his pitch usage, he will be a pitch to contact guy. There simply is no way around that. His K rate may rise slightly, but he will still be a below average strikeout pitcher unless he alters his pitch mix.

Stroman’s walk rate this season has been disappointingly high (7.1%, 2.19 K/BB). He has always been fantastic at limiting walks at all levels of his professional career. Usually, his walk rate hovers around 6%. That might not seem like a big difference, but for a pitcher who is only striking out six batters per nine, a 1% rise on the walk rate is significant.

This elevated walk rate may be a little misleading, however. Stroman tends to nibble at the edges of the zone, even with two strikes. He has not been as efficient in the strike zone with his sinker this season, so that has hurt him somewhat. Also, he recently had a 5 walk outing against the Red Sox. If we simply removed that start from Stroman’s numbers, his BB/9 would be 2.36, which is much closer to his career norms.

I expect Stroman to improve marginally in both areas if he continues with the same pitch mix. His walk rate should definitely improve, but he needs to be a little more aggressive early in counts. If he is able to get ahead, he can turn to those nasty off speed pitches which will allow him to get a few more strikeouts. Stroman’s control is too good to have such a low K/BB ratio. I expect closer to 3.0 as the season moves along.

If Stroman changes his pitch mix a bit, he could improve further on the K rate and get back up in the neighborhood of 8.00 K/9. I would like to see him throw fewer cutters, and more sliders/curveballs. I do not think the cutter should be a featured pitch for Stroman. His other off speed offerings are much better.

Batted Ball Data

Marcus Stroman makes his living off of an insanely high ground ball rate. This season, opposing hitters are killing worms 59.2% of the time, which is right in line with his career numbers. Since all of his pitches tend to sink significantly, this should come as no surprise. His line drive rate is near league average and his fly ball rate is far below. Typically, Stroman is a master of inducing soft contact, but that has not necessarily been the case this season. His hard contact rate is up to 32.4%, which is far higher than it was either of the past two seasons.

When you add it all up, Stroman is a pretty average BABIP guy. The low fly ball rate tends to inflate BABIP, but the soft contact counters that somewhat. His career BABIP is .299 and his BABIP this year is .306. I see no reason to expect anything significantly different moving forward.

Stroman has a higher than average HR/FB rate, but because his fly ball rate is so low, he is well above average when it comes to limiting home runs. Low home run rates have always been part of Stroman’s skill set, and I see no reason to change on that.

In summary, Stroman’s batted ball data supports that he should have a near average BABIP, which he does. His WHIP is elevated because his K/BB ratio has been so poor. His ERA is up in part because he is allowing more base-runners, but he also had some pretty terrible luck with inherited runners scoring near the beginning of the season. On two separate occasions in April, Stroman left partway through an inning with the bases loaded. The first time, he departed with 1 out and the very next batter hit a grand slam. The second time, he left with two outs and all 3 runners still managed to score.

Last 30 Days

Since May 11th against the Giants, Stroman has only made one quality start. Over that span, his K/BB ratio has been a putrid 1.61. He struck out only 12.7% of the batters he faced while walking 7.8%. His ground ball rate has been as high as ever, but the fly balls have all but disappeared. He has allowed a ton of line drives and more hard contact than normal. Not surprisingly, his BABIP has also been much higher than normal, but again, this result is due more to poor performance than bad luck.

There are not any obvious signs of injury here. Stroman’s velocity has been just fine; he just has not pitched well at all.

Final Conclusions

Here is my rest of season projections for Stroman:

  • IP: 85
  • ERA: 3.80
  • WHIP: 1.25
  • Ks: 64
  • Wins: 5

Stroman is a very talented real life pitcher, but I am not sure how much short-term fantasy value he has. He is trending the wrong way in terms of K and walk rates. I do think he will find his rhythm and improve because he is better than this, but I can’t exactly predict fantasy domination either. He relies too much on pitching to contact and will have his share of ups and downs as a result. I would be more inclined to own him in head to head leagues, but I think he may have limited value in K/9 roto style formats. He just does not get enough strikeouts.

Patrick Corbin, Arizona Diamondbacks

78.2 3 58 4.18 1.33

Much like Stroman, Patrick Corbin was a popular breakout candidate heading into the 2014 fantasy season. He underwent Tommy John surgery just prior to the start of the season, missing all of 2014 and half of 2015. He was able to make it back in time for 16 starts last year, and his numbers were better than ever. Fantasy owners were expecting Corbin to pick up where he left off, but it just has not happened that way. Let’s take a close look and try to determine why.

The Arsenal

Corbin has two fastballs that both travel in the low 90s. His velocity is down slightly from last season, but right in line with pre TJ numbers. His two-seamer is the more frequently used and more effective of the two (38.9% usage rate). It has some great sinking action and yields a high ground ball rate (64.2% GB rate in ‘16, 52.8% career). Corbin uses the four-seamer about 25.7% of the time, and it has been getting crushed this season. Opposing batters have a .431 wOBA and have already launched five home runs against the pitch. Interestingly, Corbin also found success with the two-seamer while struggling with the four-seamer in 2013, but the results were exactly the opposite in 2015. Still, his career numbers show that the two-seamer is the more effective of the two fastballs. Neither pitch is generating very many swinging strikes (both well under 5%).

Corbin’s best pitch is a wipeout slider that he throws about as often as the four seam fastball. He gets a lot of swings and misses on the pitch. This year, his swinging strike rate is an impressive 22.4%, which is actually significantly lower than his career average of 25%. When opposing batters do make contact, they tend to do so weakly. The slider yields an above average ground ball rate, and Corbin has a career wOBA of .197 on the pitch.

Corbin uses a changeup against right handers to keep them off-balance, but it is really a terrible pitch. Opposing hitters have a career .431 wOBA against the pitch, and that number is all the way up to .541 this season. The lack of a decent third pitch is a big part of the reason why the lefty Corbin struggles against right-handed batters.

Ks and BBs

In seasons past, Corbin has been able to post above average strikeout rates thanks to his dynamic slider. This season, his K rate (17.4%) has dipped below league average, and his overall swinging strikeout rate is down to 9.3%. He simply does not get enough swinging strikes on the fastball to produce much better than this. Without significantly increasing his slider usage, I think his current K/9 (6.64) is in the ballpark of what owners should expect moving forward. Seven Ks per nine is about the upper limit. When Corbin posted his career high K rate of 21.9% in 2015, he was throwing the slider 29% of the time. That is probably too high for a pitcher who recently had Tommy John surgery.

Corbin has always done a pretty good job limiting free passes, but his walk rate (6.9%) is up slightly in 2016. He has really struggled to get ahead of hitters early. His F-strike rate this season is just 56.3% compared to a 63.7% career rate. Corbin is throwing in the strike zone at about the same rate as always, but he is simply not getting hitters to chase as often (29.4 O-swing in ‘16, 34.1% O-swing career). The biggest issue here is that hitters just are not chasing the sinking fastball early in the count. This is causing him to fall behind more often, eventually leading to more walks and fewer opportunities to use the slider to put batters away.

Last year Corbin had a K/BB ratio of 4.59. That is all the way down to 2.52 this season. He should be able to improve marginally in both areas, but I would not expect a K/BB ratio much better than 3.0 moving forward.

Batted Ball Data

Corbin has always had a ground ball tilt to his batted ball profile, but has enjoyed pretty average batted ball luck with a career BABIP of .300. This season his ground ball rate is a up a bit to 53.2%, and his BABIP is actually down to .293. The number that absolutely leaps off the page, however, is Corbin’s hard contact rate of 39.4%. Considering that league average is about 30%, that presents a pretty big problem. Given such a high hard contact rate, Corbin may be getting lucky with his BABIP.

Where Corbin is not getting lucky is on his homerun rate. He is allowing a 17.9% HR/FB rate and a HR/9 of 1.37 despite a relatively low fly ball rate of 27.3%. While normally I would chalk that up to bad luck, I am not so sure given the hard contact rate. All of Corbin’s ERA indicators are higher than they have been in the past due primarily to his low K/BB ratio. His xFIP sits at 3.98 which indicates that Corbin has pitched better than his current ERA. Given the hard contact rates, I would disagree. I actually think Corbin is somewhat lucky to have an ERA below 5.00.

I would like to be able to say that Corbin’s elevated ERA is a by-product of batted ball luck, but I can’t do that. Hopefully, his HR/FB rate will come back down to earth, but if he cannot limit the hard contact, his ERA will remain substantially higher than his xFIP.

Split Stats

Corbin has always had a difficult time against right handed batters. His career wOBA against righties is almost .50 points higher (.327 vs righties, .278 vs. left). This season, the disparity is about the same, but both numbers are higher. The main difference is that 11 of his 12 home runs have come against righties and his K% against righties is only 13.8%, vs. 31.8% against lefties.

Although this has not been true for his career, Corbin has struggled mightily at home this season. His road numbers actually jive pretty well with his overall career totals. At home though, Corbin sports a 7.53 ERA and a .405 wOBA against. His two most severe shellings along with 9 of his 12 home runs allowed have occurred at home.

Final Recommendations

Here is what I am projecting for the rest of the way:

  • IP: 85
  • ERA: 4.00
  • WHIP: 1,30
  • Ks: 65
  • Wins:4

Corbin’s skills have regressed to the point where it is fair to question whether or not he should be owned in mixed leagues. I would suggest holding on in leagues of 14 or more for now, but owners in shallow leagues can feel free to drop him if you see someone better on the wire. He simply does not have enough trade value to justify holding him.


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Tommy Landseadel

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Tommy is also known as tlance on the CBS and Sports Hoopla message boards. He has been playing fantasy baseball for 16 years in many different format types and looks forward to helping you with your fantasy baseball questions! You can now follow me on Twitter @tlandseadel