Nix said he was practicing at first base “just in case.” But it could also give the Nationals a way to keep Nix in the lineup if his sore right Achilles’ tendon continues to hinder him.

Nix left the first game of yesterday’s doubleheader, the third time this month he has to leave with tightness in his Achilles’. Morse could switch back to left field if and when Nix plays first, a swap that would hurt the Nationals at two defensive positions but would allow the Nationals to put two powerful bats in the lineup while giving Nix a better chance to keep his Achilles healthy.

After he took a few grounders, Nix was asked if he had played first before. “Yeah,” he said. In the majors? “No,” he replied. “High school.”

Still, Nix is a better athlete than his size lets on, and he has practiced at first in the past with the Reds. “For having not played,” Nix said, “I feel pretty comfortable doing it.”