Gary Sanchez and the Yankees felt the All-Star catcher was a bit too bulky last season.

So he took action.

Sanchez will go into spring training about 20 pounds lighter -- and noticeably slimmer in the waist -- than he was last spring, according to a source close to the 25-year-old. He was approximately 235 pounds in February 2017.

But Sanchez hasn't lost any of the power that helped him mash 33 home run and 90 RBI despite missing a full month due to injury, the source added.

Last August, general manager Brian Cashman said he believed Sanchez put on too much muscle and that it was hurting him behind the plate. Sanchez allowed 16 passed balls, tied for the league-worst mark with the Dodgers' Yasmani Grandal, who caught about 118 innings more than Sanchez. Then-first base coach and catching instructor Tony Pena also attributed Sanchez's woes to concentration.

The ball-blocking problems even led then-manager Joe Girardi to start backup Austin Romine at catcher over Sanchez for two games in Cleveland.

The source said Sanchez and the Yankees agreed that his added muscle had affected Sanchez's ability to get down and block balls as fast as he's truly capable.

Sanchez is expected to arrive in Tampa, Florida, for spring training on Sunday, the source said. He's spent almost all offseason in the Dominican Republic.

Yankees pitchers and catchers are to report to George M. Steinbrenner Field on Tuesday with their first workout Wednesday.

The rest of the position players will report Feb. 18. The first full workout will happen Feb. 19.

Brendan Kuty may be reached at bkuty@njadvancemedia.com. Follow him on Twitter @BrendanKutyNJ. Find NJ.com Yankees on Facebook.