Pittsburgh Pirates pitcher A.J. Burnett reached a milestone during the first inning of Sunday’s 4-0 loss to the Chicago Cubs, becoming the 32nd pitcher in MLB history to record 2,500 or more career strikeouts, per MLB Stat of the Day.

Entering the contest with 2,499 strikeouts, the 38-year-old Burnett got off to a rocky start in the first inning, allowing four of the five batters he faced to reach base.

With one run already in and the bases loaded, Burnett got ahead in the count against Cubs outfielder Jorge Soler, who foul-tipped a 1-2 pitch into the glove of Pirates catcher Francisco Cervelli for the milestone strikeout.

Burnett then induced a groundout from Cubs catcher Miguel Montero to end the inning, but Cubs pitcher Jake Arrieta hit a solo homer in the bottom of the second to extend the lead to 2-0.

Burnett did settle down to hold the Cubs scoreless over the next four frames, eventually finishing with five strikeouts in six innings, allowing just two runs on seven hits and two walks.

While always above average at striking batters out, Burnett took the slow-and-steady path to 2,500 if compared to most of the other pitchers who have reached the mark.

He only has three 200-strikeout seasons among his 17 MLB campaigns, with those coming in 2002 (203), 2008 (231) and 2013 (209).

He does, however, have 12 straight seasons with triple-digit strikeouts, as he’s made 20 or more appearances every year since 2004.

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