The St. Louis Cardinals got a great performance this year from Joe Kelly. The right-hander put up a 2.69 ERA in 124 innings, including 15 starts. In his starts he had a 2.28 ERA, while he posted a 3.65 ERA in 37 innings in relief. Against the Pittsburgh Pirates, Kelly had a 2.53 ERA in 21.1 innings, with a 16:10 K/BB ratio. Today Kelly will go up against the Pirates in Game 3 of the NLDS.
The ERAs look great, but when you dig deeper into the advanced metrics, you'll see that Joe Kelly is a regression candidate.
On the season, Kelly has a 4.19 xFIP, which is 1.5 runs above his ERA. Out of all pitchers in the majors this year with 120+ innings pitched, Kelly has the second biggest difference between his ERA and his xFIP.
Kelly has a dominant ERA, but he hasn't been dominant on the mound. As a starter he has a 4.76 K/9 and a 3.52 BB/9 ratio. A 1.35 K/BB ratio doesn't usually lead to a 2.28 ERA. First you've got the low strikeouts. That means you're relying too much on your defens...
Tim is the owner and editor in chief of Pirates Prospects. He started the site in January 2009, and turned it into his full time job during the 2011 season. Prior to starting Pirates Prospects, Tim worked with AccuScore.com, providing MLB, NHL, and NFL coverage to various national media outlets, including ESPN Insider, USA Today, Yahoo Sports, and the Wall Street Journal. He also writes the annual Prospect Guide, which is sold through the site. Tim lives in Bradenton, where he provides live coverage all year of Spring Training, mini camp, instructs, the Bradenton Marauders, and the GCL Pirates.