NEW YORK _ Aaron Judge's "lower body tightness" became more defined on Friday, when the Yankees slugger landed on the 10-day injured list.
Leading the majors with nine home runs, Judge was diagnosed with a "very mild strain" of the right calf, according to manager Aaron Boone.
An MRI conducted Thursday revealed the strain.
"He wants to be out there and feels like it's a day-to-day thing, which it very well may be," Boone said Friday evening.
"But it goes without saying how important a player Aaron is to us," Boone said. "It's really important that he not go out there and hurt this thing significantly, trying to play through something."
The Yankees recalled infielder Thairo Estrada prior to Friday night's four-game series opener against the Red Sox at Yankee Stadium.
"Lower body tightness" had been the rather opaque description of the slugger's condition by Boone, who pulled Judge out of Tuesday night's game against Atlanta _ immediately following his MLB-leading ninth homer of the year.
Judge was removed for a pinch-hitter with the Yankees leading 8-3 in the sixth inning, a game they won 9-6.
Judge received treatment and did not play in Wednesday night's 6-3 win against the Braves. Thursday was a team off day.
Initially, after subbing out Judge Tuesday night, Boone said he was taking advantage of an opportunity to get Judge off his feet following a four-game series on the artificial turf at Tampa Bay.
Before Wednesday night's game, Boone revealed more about what appeared to be a strange decision at the time.
"I made a quick decision in the game just based on how I felt he was moving around," said Boone, adding that Judge experienced "some wear and tear" playing four games in three days at Tropicana Field, including a doubleheader Saturday.
"We're hoping to get out ahead and hopefully prevent an injury moving forward," Boone said earlier. Giancarlo Stanton is for the next three to four weeks due to a strained left hamstring.
