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Clay Buchholz is having a tough 2014 season. That is putting it mildly. His ERA of 6.32 is a far cry from his 2013 ERA of 1.74. His WAR, while still positive, sits at 0.4 (it was 3.2 last season). In many ways, Buchholz’s decline has mirrored the struggles of the Red Sox. The Boston Red Sox have gone from 2013 World Series Champions to cellar dwellers in the A.L East. Unfortunately for Red Sox Nation a turnaround does not appear imminent for the team or for Buchholz.

While there are many issues driving the poor performance of the 2014 Red Sox, one of the big ones has been the extreme decline in performance from Buchholz. Let’s take a look at the changes between 2013 and 2014 to see what’s going on.

While there are many issues driving the poor performance of the 2014 Red Sox, one of the big ones has been the extreme decline in performance from Buchholz. Let’s take a look at the changes between 2013 and 2014 to see what’s going on.

There has been a lot of talk in the media about Buchholz leaving pitches up in the zone this year. Manager, John Farrell recently discussed this issue after Buchholz’s 5/21 start against the Blue Jays that resulted in a 6 – 4 loss for the Red Sox and a pitching line for Buchholz that included 9 hits and 5 runs (4 earned) over only 4.2 innings.

“So when he's making mistakes, he's been up in the strike zone or he's been in the middle of the plate,” Farrell commented.

Analyzing the spin on Buchholz four core pitches (fastball, changeup, curveball and cutter) starts to reveal some of the causes for his pitching woes. The chart below shows the difference in spin in the past year, which has declined in 3 of his 4:

While the spin on Buchholz’s curve and cutter are above the ML average, it is still below that of his 2013 season average (-9.4% and -11.6% respectively). We can infer from this that the movement on his curve and cutter has similarly decreased. In addition, the spin on Buchholz’s fastball is down -11.7% year over year and below the MLB average.

Sure enough, the movement and break data confirm my suspicions:

While there is degradation in the horizontal movement numbers (first number in the set) it is minor (and non-existent for the cutter). The real issues with Buchholz’s pitching seems to be vertical movement decreasing (second number in each set). The vertical movement for each of the three pitches above has decreased bringing all of them closer to the center of the strike zone, just as John Farrell had suggested in his remarks to the press.

While we’re on the subject, it is worth noting that one of the reasons commonly cited for Buchholz’s success in 2013 was pulling back the velocity of his cutter by ~1.6 mph (89.4 mph to 87.8 mph) while increasing horizontal movement from 1.8” to 3.5” – a big improvement that led John Farrell to remark:

“When you reduce the velocity, you're probably going to increase the break. Those go hand in hand. So, this is more about Clay getting a better feel for his pitch mix and what he's determined to be most effective in the four-pitch mix that provides more definition in keeping his fastball and cutter from blending into each other.”

Buchholz has maintained a 3.5” horizontal movement on the cutter in the 2014 season but he has lost some of the vertical movement (- 0.9”). In addition, the average velocity of Buchholz’s cutter has dropped another 1.1 mph. In other words, as his cutter has been hanging up in the zone, the average velocity has also decreased. The same is true of his other three core pitches.

While all four core pitches have degraded this year, the cutter is particularly worrisome for Buchholz. Buchholz is not generally a power pitcher (especially not this year as his fastball velocity has dropped an additional 1.1 mph). He relies on movement to win games. Perhaps this is why Buchholz has used his cutter more this year (31% of pitches in 2014 vs. 24% of pitches in 2013) even though its effectiveness has decreased.

We can see the decrease in effectiveness of all pitches when looking at runs above average per 100 pitches in the chart below:

The chart clearly shows the lack of effectiveness Buchholz has shown this season. However, it also shows that the cutter is still his best pitch, which is possibly why he is increasing its use this season.

Before concluding we should address the idea that has been espoused by a number of folks this season - that Buchholz has been hurt by some bad luck and perhaps his team’s issues with fielding. Let’s take a look at that through the lens of FIP.

It appears that there is some truth to the idea that Buchholz has been hurt by some bad luck and/or bad fielding. His 2014 FIP is 4.58 while his current ERA is 6.32. The Red Sox are currently 20th in the MLB in fielding percentage where they were 9th last season which explains the difference between ERA and FIP.

Buchholz is clearly off his 2013 form and his team’s fielding woes are compounding his issues. However, the big picture story seems to show that 2013 was an outlier season for Buchholz (typically a ~3.8 ERA pitcher – his average from 2008 - 2013) and conceivably this season is just part of regressing to his overall career mean.

NOTE: All statistics accurate as of 05/26/14

By By Eric Olson
AriBall.com

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