Pitching was not exactly a strong point for the Detroit Tigers during the 2020 season, with a staff that finished last in the majors in ERA (5.63) and ERA+ (84), second last in strikeouts (444) and FIP (5.17), and gave up the fourth-most home runs (91), among many other miserable stats.
But do not let the introductory paragraph discourage you — there were a few bright spots among the Tigers’ hurlers this past summer. Among those was a right-hander known for both his fiery hair and fastballs, who earned the title of de facto ace with his solid season wearing the Olde English D.
Spencer Turnbull is his name and throwing baseballs is his game.
The Red Bull led all regular starters with a respectable 3.97 ERA, 118 ERA+, 3.49 FIP (third-best overall on the team), and 1.34 WHIP, along with two home runs allowed for a rate of 0.3 dingers per nine innings. He also proved his mettle by starting 11 games — just one short of Matt Boyd’s team-leading 12 — throwing a total of 56 2⁄3 innings, which was also second on the team after Boyd. Suffice to say, traditional metrics spoke highly of Turnbull in comparison to his Tigers peers.
However, among the rest of his MLB colleagues, if Spencer had thrown 1 1⁄3 more innings to qualify, he would rank 28th in ERA between German Marquez and Jose Berrios, his WHIP would tie Martin Perez’s mark at No. 34 and he would tie Dallas Keuchel — who threw 6 2⁄3 more innings — for fewest home runs allowed. Save for that last number, the traditional stats in comparison to his peers look immensely mediocre.
Now on to some basic physical measurements of his pitching — specifically his pitch proclivities and velocities. In 2020, according to FanGraphs Turnbull threw his four-seam fastball 44.8 percent of the time at an average velocity of 94 mph, while throwing his sinker and slider 21.7 and 20.4 percent at 95.1 and 85.6 mph, both respectively. He threw his changeup a career-high 8.7 percent with an average velo of 87.4 mph and culled back his 79.6 mph curveball usage to just 4.4 percent — a career low. The biggest change from 2019 was the added emphasis on the offspeed pitch while cutting back on the curve, but he also added a tad bit more mustard to his fastball and offspeed offerings.
Spencer Turnbull, Disgusting 96mph Two Seamer. pic.twitter.com/PWbeClmoRt— Rob Friedman (@PitchingNinja) September 3, 2020
Overall, Turnbull accumulated 1.4 fWAR — almost double José Cisnero’s 0.8, second among hurlers — to lead the pitching staff; only Jeimer Candelario had a higher fWAR value (1.6) and Spencer’s mark happened to match Jonathan Schoop’s to tie for No. 2 on the team. The Red Bull’s 1.1 bWAR claimed sole possession of second place again to Candelario (1.6). At a base salary of $573,500 before 2020 proration, Spencer provided a great deal of value to the Tigers this summer.
Having surveyed the traditional means of evaluating a player, we move on to what modern technology can tell us about Detroit’s best starting pitcher this season. Taking a look at StatCast numbers over 963 total pitches, many of the metrics look mediocre, but a few things do stand out.
The good news was that Turnbull’s average launch angle of 8.5 degrees is second-lowest on the team only to Daniel Norris’ 7 degrees among pitchers with more than 400 pitches — this agrees strongly with the home run suppression seen in the traditional stats. This is also consistent with a long-running skill that dates back to Turnbull’s minor league career as well. Conversely, his average exit velocity of 91.1 mph (up from 89.6 mph in 2019) was among the bottom 8th percentile in the league, which means despite putting a little extra on his pitches and mixing things up a little differently this year, he was hit hard.
The exit velocity problem was fortunately the worst of Spencer’s worries, though he lagged on the lower end of StatCasts’ percentiles in hard hit, xwOBA, xERA and BB (18th percentile), as well as xBA (16th percentile), strikeouts (35th percentile) and xSLG (38th percentile). On the brighter side, his fastball spin rate was in the 84th percentile, and though sparsely used, his curveball spin rate came in at a modest 71st percentile. His fastball velocity, whiff percentage and barrel percentage were ranked in the 66th, 60th and 59th percentiles, respectively.
Spencer Turnbull, Nasty 86mph Back Foot Slider. pic.twitter.com/BcrhtJYIIR— Rob Friedman (@PitchingNinja) September 19, 2020
Taking things one step deeper, a look at his pitch tracking numbers showed that his slider was his most unhittable pitch, drawing whiffs 43.6 percent of the time, followed by his seldom-used curveball (33.3 percent), trusty four-seamer (28.1 percent), scalding sinker (17 percent) and revived changeup (14.3 percent). His putaway percentages on his four-seam, curve and slider were just about even at 23.2, 22.2 and 22.0 percent, respectively. While Turnbull could draw some whiffs, he did not have a true finishing pitch, as evidenced by his mediocre strikeout total.
Spencer Turnbull was undoubtedly a bright spot for a Detroit Tigers team that was not very good in 2020, but much of that can be credited to the low bar he faced with a statistically abysmal group of pitching peers. One of the limitations of this review, of course, is the reduced sample size afforded by the coronavirus-affected season, which limited the team to just 58 total games — or just over 36 percent of a regular, non-pandemic season — but reasonable conclusions can still be derived by comparing to other players facing the same stipulations.
At the end of the day, the Red Bull was a serviceable starter who would probably land in the middle of the rotation on a competitive team and since he is still under team control — his first year of arbitration is not until 2022 — he provides plenty of surplus value. Turnbull could make for an intriguing trade piece to entice a franchise looking to bolster its starting corps, or the Tigers can hang on to him and milk a couple more years of production out of him — after all, he is in his prime at 28 years old and the team is in dire need of some stability on the mound.
However the future shakes out, the numbers will forever show that Spencer Turnbull was Detroit’s starting stud this season. Hopefully the flame-haired fireballer can continue to improve and help guide the Tigers out of the rebuild into postseason contention, or at very least provide a piece of the future puzzle otherwise.