Prospect Profile: Patrick Corbin, LHP, Arizona Diamondbacks


The dog days of summer are upon us and all across the major leagues teams have been buying and selling in attempts to improve their chances either for a playoff push or to rebuild for future success. This was especially evident in the AL and NL West divisions where multiple teams have made big splashes on the trade front.

As it sits now in the AL West the Rangers tried to separate themselves from the pack with the acquisition of starting pitcher Ryan Dempster while the Los Angeles Angels made a huge splash with the acquisition of starting pitcher Zack Grienke in an effort to bolster their rotation for the stretch run. Likewise in the NL West the Dodgers were very active at the deadline adding talented 3B/SS Hanley Ramirez and starting pitcher Joe Blanton while the rival Giants countered by adding right-fielder Hunter Pence to help aid their floundering offense. While each of these playoff contenders made some big moves, they were far from alone in adding talent at the deadline; even within their own divisions.

In the AL West the Oakland A’s, who are currently half a game out of the Wild Card, decided to not engage in any major acquisitions at the deadline choosing instead to rely on internal options and the recovery of some of their key players. The A’s promoted fast rising pitching prospect Dan Straily (perhaps a bit premature as he has since been sent back to refine his skill) and are going to lean heavily on Brandon McCarthy and Brett Anderson down the stretch. In the NL West the Diamondbacks decided to bolster their team in a similar fashion by calling up the solid, but less hyped, starting pitcher Patrick Corbin from Triple-A. Prior to the 2012 season Corbin had been a relatively unknown quantity buried behind the starting pitching depth in his respective farm system but that no longer is the case.

The left-handed Corbin, 23, was drafted in 2009 by the Los Angeles Angels in the second round out of Chiploa College in Florida. He signed quickly enough to work 46 1/3 innings in 2009 in Orem of the Pioneer Rookie league. He posted solid SO/9 ratio of 8.9 and a decent BB/9 of 2.1, leaving him with a strong SO/BB of 4.18. However he allowed way too many hits (11.5 H/9) and home runs (1.2 HR/9) which caused his bloated ERA of 5.05 and a 1.51 WHIP.

In 2010 Corbin was promoted to Class-A Cedar Rapids of the Midwest League. He made nine starts for the Kernels and pitched to an 8-0 record and 3.86 ERA. Perhaps most impressively he had a 1.5 BB/9 ratio which allowed him to post an outstanding 4.20 SO/BB ratio despite striking out what has turned out to be a career low 6.5 SO/9 and in the process earned himself a promotion to the hitter friendly CAL League. While a member of the Rancho Cucamonga Quakes, Corbin made 11 starts and posted a 3.88 ERA and dramatically improved his strikeout rate from 6.5 to 9.5 SO/9. He only surrendered seven long balls over 60 1/3 innings – an accomplishment in itself in that environment. As fate would have it his time with the Quakes was cut short as he was traded along with Tyler Skaggs, Rafael Rodriguez, and Joe Saunders to the Arizona Diamondbacks for Dan Haren. Corbin would go on to make eight more starts in the CAL League this time for Diamondbacks affiliate the Visalia Rawhide. In those eight starts Corbin logged 26 innings and an impressive 1.38 ERA and saw his SO/9 ratio rise again this time from 9.5 to 10.4. For those keeping track at home, Corbin logged 86 1/3 innings in the CAL League and posted a very strong 3.13 ERA to go along with solid peripheral numbers including 9.8 SO/9 and 3.48 SO/BB rates.

In total Corbin’s 2010 season was a whirlwind but in a good way. He started 26 games across two levels and pitched for three teams. He logged 144 2/3 innings and posted a very respectable 3.42 ERA with an excellent 8.5 SO/9 and an even more impressive 3.68 SO/BB rate. The bulk of which was accumulated in a hitter friendly environment and during his age 20 season. Not bad for a relatively un-hyped prospect.

The 2011 season would see Corbin promoted to Double-A Mobile of the Southern League. As a 21 year old he would go on to make 26 starts and log a career high 160 1/3 innings. He posted a 4.21 ERA to go along with a 8.0 SO/9 and 3.55 SO/BB. Along with a mid-season Southern League All-Star selection he was also named the Southern League Pitcher of the Week three times in 2011. The only blemish to speak of was the amount of hits he surrendered.  Corbin allowed 172 total hits in 2011 which was good for the 4th highest in the league. It is however worth mentioning that he was one of 10 pitchers age 21 or younger in the Southern League and all things considered he still posted a solid, if unspectacular, season with solid peripheral numbers.

Then 2012 happened.

Corbin started the 2012 season right where he left off in 2011 back in Mobile as a member of the BayBears starting rotation. It was clear from the beginning that 2012 was going to be a season to remember and the lefty absolutely blasted through Double-A. He only pitched 27 innings over four starts but he only allowed only five earned runs on his way to posting a 1.67 ERA and a 8.3 K/9 rate. the most impressive part of his limited stint in Mobile was the dramatic improvement he made to his H/9 rate. In 2011 Corbin was allowing an unacceptable 9.7 H/9 and in 2012 he reduced that number significantly to 7.3 H/9. That 2.4 reduction was enough to earn him his first promotion to the big leagues.

He made his first career start on April 30th against the Miami Marlins with mixed results. While he was able to work 5 2/3 innings, strikeout six batters, and earn his first professional win he was unable to keep hitters off balance issuing three free passes and he surrendered eight hits including a home run to Donnie Murphy of all people.

Such was the story for Corbin during his first extended stint in the majors. He showed flashes of his potential but never really put it all together. For example, he was clobbered in his second career start against the Mets lasting only 3 1/3 innings but rebounded nicely in his third start to throw seven solid innings of one run ball against division foe San Francisco then got shelled in his next start versus the Colorado Rockies.  Ultimately the D-Backs decided to send Corbin to Triple-A Reno at the end of May to iron out a few wrinkles. His time in the PCL was short lived though as he eventually found his way back to Arizona when injuries ravaged the Snakes’ rotation. This time he performed well enough in a long relief role to merit another opportunity in the rotation. So off he went, back to the PCL to get stretched out. While there  he made a few mechanical and mental tweaks in an effort to make his second stint as a major league starter more successful and more permanent. All told he made nine starts in the PCL in 2012 and it was business as usual for Corbin as he pitched to a 3.44 ERA with a SO/9 rate of 9.5 and a SO/BB rate of 3.67, all in line with his career averages.

In his four most recent starts for the D-Backs, Corbin has been considerably more effective than his first time around. He has improved his overall command, especially with his slider, and has seen a significant increase in his swinging strikes and overall strikeouts. In his first stint as a starter he amassed 27 1/3 innings in which he surrendered a total of 16 earned runs to go along with nine walks and three home runs while only striking out 18 batters. More recently in his second stint he has pitched 26 innings in which he has only allowed eight earned runs to go along with six walks and two home runs while striking out 24 batters. The small drop in free passes along with the noticeable rise in strikeouts has been a key factor to his success. He has also had a bit of an uptick in his fastball velocity which is a factor in the swinging strikes. In his first stint he was hovering around 90.5 mph on average with his fastball and more recently that number has bumped up to closer to 90.8 mph on average. While this is just a small bump it is noteworthy because it improves the effectiveness of his secondary offerings and it has been through those offerings, again specifically the slider, that he has emerged as a more effective pitcher. One additional factor that bodes well for him is the fact that when he is taking the mound the D-Backs are winning. None of that is lost on an old school manager like Kirk Gibson who puts a lot more weight into those tangible results rather than in peripheral stats which have become the life-blood of the sabermetric community.

While the early going of 2012 was a bit rocky for Corbin he has emerged from the experience a better pitcher. If he continues to build on his success and continues to give the D-Backs a solid chance at a victory every fifth day he will quickly become a fixture in what is shaping up to be one of the younger and more exciting rotations in all of baseball. He’s already proven he can pitching the majors, and it seems increasingly likely that he will be able to reach his ceiling as a middle to top of the rotation starter. I personally look forward to watching him progress because he was one of those unique (especially in today’s game) prospects who had strong tools and the numbers to support those tools but consistently was left out of the top pitching prospect conversations. While he did appear on a few organizational top ten lists he was almost always at the bottom and received relatively little fanfare, there were some however who were bullish on the lefty prior to the season. One such person was former S2S Editor Nathaniel Stoltz who slotted him in at #83 on our 2012 Top-100 Prospect List.

Look for Corbin to continue his success against the light hitting Padres on August 24th and look for the D-Backs to continue the trend of building from within with their outstanding farm system talent and depth.


For more on Patrick Corbin and the Arizona Diamondbacks check out Venom Strikes!