Over the past four seasons Jacob deGrom has established himself as an elite pitcher, among the best in the league. He’s been known for consistency game-in and game-out, and although he doesn’t rack up the innings counts of a typical workhorse, deGrom could still earn the label, as he often pitches deep into his starts and comes through in big games.
So far this year he’s mostly lived up to that reputation, although there have been a few bumps along the way. At the beginning of the season, Ryan detailed the adjustments deGrom was making in order to continue being an elite pitcher. He started using more two-seamers to induce more groundballs, along with more sliders to induce more swings and misses, and both pitches were doing their job.
Later, Luis wrote further on deGrom, and the contrast between his positive improvement and the opposite movement on the part of his fellow staff-mate Matt Harvey. Both Luis and Ryan noted how high of a whiff rate deGrom had to start the season, and he’s sustained that. He’s currently fifth among qualified pitchers in swinging strike rate, at 14.3 percent.
While the whiff rate and strikeouts are looking good, if you check FanGraphs, MLB.com or Baseball Reference periodically, you might have seen some out of character numbers from deGrom in runs, home runs and walks, and as a result his fielding independent numbers. Despite what appears to be a pretty solid first half for deGrom, he went through a really bad streak of luck and home runs.
Between April 22nd and June 6th, deGrom had the third-highest batting average on balls in play among 74 starting pitchers, at .391. He also allowed 10 of the 14 home runs he’s allowed this season during that stretch, and 34 of the 42 runs he’s allowed so far this season.
Only Bartolo Colon allowed more earned runs during that period, and he was just designated for assignment by the Atlanta Braves. But outside of those six and a half weeks, deGrom has lived up to the nickname of “deGrominator”:
Between 4/22 – 6/11: 9 GS, 53 IP, 62 H, 34 R, 10 HR, 26 BB, 72 K
Before 4/22 and after 6/11: 7 GS, 51 IP, 27 H, 8 R, 4 HR, 12 BB, 53 K
During the bad luck streak, deGrom had a 4.42 FIP, a 5.77 ERA, and a walk rate of almost 11 percent. His home run per fly ball percentage was over 21 percent as well. Outside of the bad luck streak he had a 2.80 FIP, a 1.23 ERA, and a walk rate of about 6 percent. His home run per fly ball rate was under ten percent during that stretch.
So what caused this bad luck streak, and has it ended for good? It seems to be almost entirely the product of bad luck and circumstance, although his pitch usage also seems to have had an effect. deGrom’s batting average on balls in play spiked to a career high, and his swinging strike rate, hard hit rate, walk rate, and home run per fly ball rate all saw huge jumps. But at the same time, his contact rate fell off a cliff to a career low.
What makes me think this is almost entirely luck based is that there weren’t any changes to the sequencing or velocity or movement on his pitches. His release point never changed more than an inch or two, and although the command of his pitches is a little bit tighter now than it was during his bad streak, the pitches are still being located in virtually the same spots.
The only tell-tale sign of an adjustment of any kind is with his pitch usage, as the chart below shows. He used a near-majority of four-seamers during his bad streak and his slider second-most while he barely used the curveball, changeup and two-seamer. Outside of the bad streak he’s using still primarily four-seamers but at a much lower rate, and he’s also using his two-seam, changeup and curveball at an increased level while slightly lowering his slider usage.
During his rough streak of starts, the majority of his hits, over 64 percent, came off of his slider and four-seamer. The other three pitches were all under 17 percent each in terms of hits allowed. So it’s possible that the very small adjustments in usage have helped, as his extra base hit numbers shown below tend to suggest.
deGrom’s Extra Base Hits Allowed
Whether those slight adjustments in usage are what caused it or not, since deGrom made them at the beginning of June he’s been on a tear. He’s made four starts since then and has pitched at least seven innings in all four, and at least eight innings in three of the four. He’s also allowed one run or less in each of the four starts while walking eight batters and striking out 31 in a total of 32 innings of work.
He’s scheduled to make his next start tonight, so we’ll see if he can continue his impressive streak of seven-inning, one-run games. Regardless of whether it continues or not, I am fully confident we’re going to see the real Jacob deGrom the rest of the season, the same one we saw outside of the bad streak of luck so far this season, where he was virtually unhittable. It’s safe to say the deGrominator is back.
Ron Wolschleger is a Contributing Writer for Beyond the Box Score as well as Bless You Boys. You can follow him on Twitter at @FIPmyWHIP.