Jalen Beeks has a simple explanation for his lackluster Major League Baseball debut.

He needs to execute his pitches better.

The left-handed pitcher got a spot start Thursday night at Fenway Park, and was hit hard, surrendering six earned runs over four innings in the Boston Red Sox’s 7-2 loss to the Detroit Tigers.

Speaking to media after the game, Beeks said he was disappointed, but knew it was a mechanical issue he needed to work on. Red Sox manager Alex Cora backed his starter, saying he saw better execution after a rocky first inning.

To hear Beeks’ and Cora’s comments, check out the “NESN Sports Today” video above, presented by People’s United Bank.