Pat Corbin’s 2-Year Nightmare Ends with Independence Day Start for Diamondbacks


Pat Corbin, one of the best pitchers in baseball in 2013 before Tommy John surgery sidelined him in 2014, returned to the mound for his first regular-season start in 22 months on Saturday night.

On August 20, 2013 Pat Corbin ranked just ahead of Clayton Kershaw as the most valuable pitcher in baseball. An elbow injury nagged him. Tommy John surgery, after trudging through the remainder of the 2013 season, followed.

Corbin missed all of 2014, and has only recently taken the mound three times for the minor league Mobile Bay Bears. Encouraged by the return of fellow Tommy John-surgery alum Matt Harvey’s upper-90s fastball, the Diamondbacks watched anxiously Saturday night to see if Corbin’s accurate sinker and extremely tough-to-hit slider grants him “ace” status again. Fireworks had already started most places by shortly after 10 pm, when Corbin used his extremely effective slider to get Colorado’s DJ LeMahieu to hit into a double play.

But Corbin threw mainly fastballs in the low 90s in his first trip to a major league mound since 2013. He struck out three and allowed two runs in five innings to gain his first win since 2013 in Arizona’s 7-3 victory over the Rockies.

Flashing back to April 20, 2013, Corbin had just added a 10-strikeout, no-walk complete game in one of the toughest places to win, to give the Diamondbacks a 21-4 mark with him on the mound (84%) for a team that was 44-55 when he was not pitching. He had outdueled Kershaw 3-0 in his second start of the season, and single-handedly kept the Diamondbacks competing with the Dodgers for most of the season, causing manager Kirk Gibson’s wife to text, “Thank God for Corbin,” as reported in a great overview on Corbin’s return in Inside the Zona.

While certainly he was not as good a pitcher as Kershaw, he had been even more valuable–worth about 14 additional wins for the team (See

Since that high, it has been a nightmare.

Corbin suddenly couldn’t get outs for the last seven starts of the season. And it turned out the injury required Tommy John surgery to return him to form. He gutted out those final seven starts, and even enjoyed one good outing in which he won another pitchers duel against Dodger Hyun-Jin Ryu. With the injury not yet diagnosed in the offseason, the Diamondbacks scheduled Corbin to throw the first pitch of the 2014 MLB season in Australia in a start against Kershaw.

Critics of Value Add, such as the New Republic (see their attempted criticism refuted here), and those believing Corbin not that valuable, may want to consider the fact that the Diamondbacks compiled a 65-59 record after that great start in Cincinnati over two years ago. With him gone for the 2014 season, they didn’t win that many games all year (64-98).

No one every expected the Diamondbacks to go 21-4 with Corbin on the mound, and like Wins Probability Added (WPA+), Value Add Baseball does not predict performance. It serves as a calculation to measure the ability to pull out games when your team doesn’t give you much to work with.

For example, Corbin went 6-5 when Arizona scored between one-and-three runs for him in 2013. Just for comparison, Kershaw, clearly the most dominant pitcher, pitched for a 4-10 record when given one-to-three runs in 2013.

Pitching injuries may be the scariest in all of sports because of what is required of a pitcher’s arm, but if he can give them anything close to what he showed in 2013 it could be a game-changer for the club that could get to .500 this weekend with two wins.

The analysis of basketball, football and baseball players are intended to be neither too hot nor too cold–Hundreds immerse themselves in studies of stats not of interest to broader fan bases (too hot), while others still insist on pure observation (too cold). A healthy balance provides a much larger audience with a basic understanding of how valuable players are despite playing different sports, positions, and against different levels of competition.