WASHINGTON (CBSNewYork/AP) — New York Yankees center fielder Jacoby Ellsbury is heading to the 15-day disabled list with a sprained right knee after getting injured Tuesday night during an 8-6, 10-inning loss to the Washington Nationals.

Outfielder Slade Heathcott, a first-round pick in 2009, was called up from Triple-A Scranton-Wilkes-Barre on Wednesday. Pitcher Chase Whitley was moved to the 60-day disabled list to make room for Heathcott on the 40-man roster.

“If we are going to lose him for some time, somebody’s got to step up,” Yankees manager Joe Girardi said of Ellsbury. “That’s the bottom line. It’s part of the game.”

Ellsbury, New York’s leadoff hitter, left Tuesday’s game in the fourth inning after Girardi noticed the player seemed hurt while batting.

Ellsbury walked in that inning, then moved to second on a groundout. That’s when Girardi and a team trainer went out to visit him. But Ellbury stayed in, wound up scoring, then left before the bottom of the inning.

“I went out and talked to him and said, `Are you in a lot of pain?’ And he said, `No, not really.’ And then I said, `Can you run?’ And he said, `Let me see. Let me get through this inning and let me see.’ And when he got in the dugout,” Girardi recounted, “we just said, `That’s it.'”

Ellsbury entered the game with a team-leading .327 batting average.

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