The Milwaukee Brewers were one of the most active sellers at trade deadline, moving three veteran pieces. Closer Will Smith was sent to San Francisco, setup man Jeremy Jeffress was sent to Texas, and the team was so active in trade talks over Jonathan Lucroy that they actually moved him twice.
The trades of Smith and Jeffress threw the bullpen into flux, but for some reason, no one's really followed up on the late August and September bullpen machinations of a team 28 games back in the division. I can't imagine why. I, on the other hand, endeavor to be interested in such things.
That is why I find myself writing about Tyler Thornburg. He's an undersized right-handed reliever and former top-100 prospect who has battled consistency and injury throughout his five year MLB career. However, following the trades of the more veteran relievers, he has slid comfortably into the closer's role in Milwaukee. Since the beginning of August, Thornburg has not entered a game before the eighth inning and has collected the first eight saves of his Major League career.
It's the culmination of a season of elite relief for Thornburg, who has produced a 33.9 percent strikeout rate and earned a strong 77 DRA- over 57.2 innings. Early in the season, Thornburg credited a regular, full offseason of training for his rebound (he had been unable to lift weights due to injury rehab before 2015) — and his 95.2-mph average fastball velocity is back in line with (and even higher than) his prior 2014 highs. However, there are some significant reasons to believe that separate adjustments have had just as much or more of an effect than the renewed health.
When we peruse PitchFX data, it is clear that his velocity is at career highs across the board. While his fastball is roughly in line with past highs, his changeup and curveball velocities are each noticeably higher than ever before. He's also added spin to all of his pitches, which appears to show up in their respective movement.
|Spin Rates (rpm)||Fastball||Curveball||Changeup|
The fastball has a career-high 11.7 inches of rise, while the curveball has added more than an extra inch of drop over last year (also a career best). The resulting 21 inches in break separation has the potential to make hitters' lives very difficult, as does the over five inches of drop between the fastball and changeup. Additionally, the fastball has suddenly added explosive life — over two inches more horizontal movement than in 2015.
Maybe improved health has caused the improvements in spin and velocity, but as these are all career best rates, we also may be looking at the natural development and improved feel of a pitcher entering his age-27 season. However, what has always been a more of a problem than Thornburg's stuff (it has always been good) has been his command, and it looks like he may have addressed that noticeably through his delivery as well.
His arm slot has dropped to what is clearly the lowest point of his career. That is significant because the Brewers in recent years have been coined by some as an "over-the-top shop". This means that there is (or at least, was) an organizational propensity toward starting pitching prospects with very high arm slots. This would sometimes be accomplished by introducing significant spinal tilt to a delivery in the name of getting more downward plane on the baseball. The problem is that this negatively affects posture and balance, making deliveries that are more difficult to repeat.
It's a well discussed phenomenon that was seen in a wide range of pitching prospects such as Yovani Gallardo, Wily Peralta, and Marco Estrada. Thornburg has it as well. However, while his release point is still pretty high, it is noticeably lower than it was in 2014. I'm not a mechanics expert, but it sure looks like Thornburg's arm is lower and his head is slightly more upright, adding more balance to the movement. The left shows a fastball from April 2014, while the right is an August 2016 heater.
Additionally, his recent delivery displays a smaller leg kick, lower hands, and what looks like fewer moving parts. Again, I'm not an expert, but I'll recklessly hypothesize that these are attempts to simplify the delivery. I might also hypothesize even more egregiously and say that this is a further attempt to create a more repeatable delivery.
It hasn't shown up much in his 9.1 percent walk rate (only modestly lower than his career 9.9 percent rate), but its results are likely seen in Thornburg's improved strike rate, significantly higher pop-up rate, and career high whiff rate. It can probably be seen in his career-high (and climbing) reliance on his fastball.
His command is still no elite tool, but if his delivery is more repeatable and ability to throw strikes has improved, Thornburg's explosion of stuff makes for a pretty effective back of the bullpen piece.
He'll probably be included in the third Jonathan Lucroy trade.