Aroldis Chapman has been putting up eye-popping numbers out of the Cincinnati bullpen, and has probably ranked as the best reliever in the major leagues so far. He ranks 4th in baseball in the shutdown statistic, which credits a reliever for increasing his team’s chances of winning a ballgame. This also means that Dusty Baker has been using Chapman during high-leverage situations, a smart move with your best reliever. His regular statistics have also been fantastic, in 21.1 innings he has a 0.00 ERA, while allowing 7 walks, 7 hits, while striking out an astounding 38 batters.
He was also given the Cuban Missile nickname for a reason, and this season his average fastball velocity has been 98.3 mph, best out of all relievers. He’s actually dialed his velocity back a little this season in order to have a bit more control, and the strategy is working. Chapman is averaging a career best 3.1 walks per 9 innings, down from the 7 he allowed 1 year ago. That has allowed his K/BB rate to go from a below-average 1.73 to an elite 5.14. By keeping few runners off the bases, Chapman has yet to be scored upon, and has been the most valuable reliever in the major leagues to date. So why aren’t the Reds using him as a starter?
Mike Leake has been the 5th starter for Cincinnati this season, with disastrous results. He has been battered around on the mound and the Reds have lost 5 of the 7 games that he has started. Leake averages a meager 5 strikeouts per 9 with a WHIP of 1.59, meaning that everybody is hitting him hard. It would be a huge boost to the Reds playoff chances to get Chapman in the rotation over Leake, but Cincinnati appears scared to do so.
The Cincinnati bullpen with Chapman has been excellent this season, and could probably withstand moving its hardest thrower to the rotation. Closer Sean Marshall and Jose Arredondo both have elite strikeout rates above 11. Logan Andrusek and Alfredo Simon have also been excellent in their 32 combined innings, with a 2.53 ERA while striking out 29 batters. This unit currently ranks 1st in the National League in run prevention as well, all the more incentive to move Chapman to the rotation.
The only downside to using the Cuban Missile in the rotation could be his reliance on only 2 pitches. Chapman has thrown only a fastball and a slider since coming into the Major Leagues, and even so, he throws his fastball 83% of the time. This heavy reliance on one pitch is encouraged and very useful for a reliever, but most teams prefer starting pitchers with a larger repertoire. Chapman has one of the hardest fastballs in baseball, so a reliance on the pitch isn’t an issue, but it could become one the 3rd time he goes through the lineup.
Chapman is currently on pace to throw around 80 innings out of the bullpen, but if Cincinnati were to move him to the rotation within the next month, they may be able to get 140-150 innings out of Chapman. Cincinnati should hand those 60-70 innings over to Chapman, rather than continuing to use Mike Leake as the 5th starter. they could lead the Reds to 3-5 more wins, which could be crucial for a playoff birth. More than likely the Reds will stick with Leake and more of the same, which could cost them in a winnable division.