“It’s been nagging me the last couple months,” Nix said. “I’ve just been getting through it. It just tightened up tonight. I don’t want to push it right now at this point and miss more time.”

Nix said he’s rested two or three games this season after feeling the back of his heel tighten. Tuesday, he felt discomfort throughout the game, and then he felt the Achilles stiffen as he walked into the dugout after his last at-bat.

Jerry Hairston replaced Nix in left field. In the ninth inning, Hairston’s two-out, RBI single helped spark the five-run, ninth-inning comeback that gave the Nationals’ their ninth win in 10 games.