Craig Kimbrel was tremendous last year, posting a 2.10 ERA and 1.52 FIP over 77 IP. Some thought the “heavy” workload would lead to a drop in success this year. It seemed unlikely that he could sustain a 40% K rate and his 10% BB rate was by far his lowest figure since his first professional year. Well, they were right in saying he wouldn’t be the same pitcher.
Kimbrel has stepped it up even further: 48% K, 7% BB, and a 10% rise in groundballs. His 1.29 ERA is again a bit unlucky, posting a 1.00 FIP and 1.12 xFIP. His first-pitch strike percentage has skyrocketed from 56% to 69%. While his season numbers are stellar, Aroldis Chapman has essentially matched him this year.
However, since May 18, Kimbrel has a 0.62 ERA, 0.49 FIP, and 0.36 xFIP over 29 IP. He has allowed two runs during that stretch, both on solo home runs. The main source of those ridiculous numbers are a 52:1 K/BB ratio. Having faced 95 batters in this span, that translates into a 1.1% BB rate and 54.7% K rate. Even Chapman hasn’t posted that kind of stretch, though his current 6 BB, 56 K stretch his last 109 batters faced is still crazy.
Over the course of history, Kimbrel’s 2012 FIP rates second all-time behind Eric Gagne‘s 0.86 mark in 2003. Amazingly, Chapman and Huston Street currently occupy the third and fourth spots with their performances this season, though it is unlikely all three of these relievers are able to maintain such a pace. With Kimbrel only on pace to barely crack 60 IP, this season doesn’t rank up with Gagne and other great reliever seasons with 80+ IP (or Mike Marshall‘s 208 relief IP in ’74), but two years after making his major league debut, he may now be considered the best closer in the game.