Most baseball experts would agree that the strikeout is the worst possible result for a team batting – an out is recorded, no runs score, and no base runners advance. While ERA is the “sexy” pitching stat, it’s strikeouts-to-innings pitched that can tell you how effective a relief pitcher is at keeping runs off the board and base runners where they stand.
Rick Ingalls, a scout with the Cincinnati Reds, prefers strikeouts-to-innings pitched, or K/9, to similar metrics to gauge the efficacy of relief pitchers. “It means there must be a fastball or a slider or split-finger, whatever the pitcher throws, [and] he’s missing bats,” said Ingalls. “If a reliever has a plus fastball (velocity) and a plus slider, they have a chance to pitch out of the bullpen in the big leagues because their stuff is above average.”
Of course a team’s relievers’ K/9 metric won’t determine overall success or failure, but the Phillies relief corps has been a surprising bright spot this season. So I wanted to see where the team’s relievers stood in K/9 through March/April this season and last season, with respect to the March/April National League averages.
As you can see from the chart, the Phillies relievers are above average so far this year for K/9, ranking third in the NL behind the Cubs and Mets.
While not taking any credit away from the Phils, their relievers’ K/9 may be slightly inflated. They’ve pitched against two teams so far (Brewers and Padres) whose plate appearances end in a strikeout a quarter of the time (25.9% and 25.3% respectively). These numbers are also worst in the NL.
Can the Phils’ relievers keep this pace up with respect to K/9, or will it normalize to league average by the All Star break? Let me know what you think.