Red Sox: Joe Kelly’s low strikeout rate is becoming a concern

This isn’t to say that Kelly has been awful this season. In fact, his 1.50 ERA and 1.08 WHIP are among the best on the team and right in line with his results after being converted to a reliever late last season.

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The difference is that Kelly struck out 21 batters and only walked five over 17 2/3 innings out of the bullpen last season, showcasing the potential that enticed the Red Sox into believing he could thrive as a power arm they could unleash late in games. This year his strikeout rate has not only plummeted, he’s also walked more batters (6) than he did as a reliever last year in nearly half as many appearances.

He may currently be sporting a shiny ERA, yet we can’t help but wonder how much of that is attributed to luck. His .189 BABIP is tied for the ninth lowest in the league and well below his career .300 BABIP, which clearly indicates this rate isn’t sustainable. His 5.02 xFIP paints a far less appealing picture of what his numbers could look like if his fortune on balls hit into play were to take a turn for the worse. The only way to improve that inevitability is to cut down on the walks and improve his strikeout rate.