Brian Cashman had never fired a manager or coach within the regular season of any of his first 25 years as general manager of the Yankees.

Until now.

Hitting coach Dillon Lawson will take the fall for the team’s first-half hitting woes, as the Yankees announced he was relieved of his duties after Sunday’s 7-4 loss to the Cubs.

The Post’s Jon Heyman first reported the move on Twitter.

“It has been well documented that I have been reluctant in the past to make changes to our coaching staff in ‘the middle of a season,’ ” Cashman said in a statement. “I am a big believer that successes and failures are collective efforts.

“However, I ultimately felt that a change was needed and that a new voice overseeing our hitting operations would give us the best chance to perform closer to our capabilities as we move forward into the second half of our season. I want to thank Dillon for all his efforts. He has a bright baseball mind that will continue to lead to a long and fruitful baseball career.”

Reigning AL MVP Aaron Judge has been sidelined for five weeks with a toe injury, but the Yankees are hitting .231 as a team with a .710 combined OPS through their 49-42 start into the All-Star break.

The 38-year-old Lawson was named the Yanks’ major league hitting coach ahead of the 2022 season after a stint as the organization’s minor league hitting coordinator.

The Yankees did not name an immediate replacement for Lawson, although the release did not mention the status of assistant hitting coach Casey Dykes or first-year hitting assistant Brad Wilkerson.