Morse was drafted as a shortstop in 2000 and came to the majors as a shortstop in 2005. He started playing outfield by the end of that year, then added third base and a little first base in 2006. He took groundballs all around the infield during practice, but rarely appeared at first. He had started 12 games at first before this season.

This year, after he lost his left field job following a slow start, Morse has seized the opportunity created by Adam LaRoche’s torn labrum, and not only by hitting .403/.422/.714 in May. Morse has played flawless defense at first base, handling every play and, according to Stats LLC, fielding every groundball hit in the first base zone. His best position these days is first base.

Morse’s best play came Tuesday night, when he fielded a chopper from Ryan Howard to his left with a man on first and fired a smooth, accurate side-arm throw to second, starting a 3-5-1 double play. The throw reminded him of his shortstop days. “It was fun,” he said.

Teammates have not been surprised by Morse’s performance at first. “He’s a good athlete,” said Jerry Hairston, whose jumping throw complete the double play Tuesday night.

While jumping around the field during his career, the constant remained Morse’s steady glove and accurate arm. His range in the outfield is a question, but he made the plays he could get to. Morse made 12 errors in 55 games as a shortstop in 2005, the last one coming on Aug. 15, 2005. In his 188 games since, he has handled 503 total chances and made not a single error.

“You can put him anywhere on the field, and he’s going to catch the ball,” Manager Jim Riggleman said. “The range issue at second and short is not going to be what Desmond and Espinosa do. If it was necessary to put him anywhere on the field except centerfield or catch, I feel like I can put him there.”

Morse has already started 12 games at first base this season, matching his previous career total. He could stay for the remainder of the season if LaRoche needs season-ending surgery, a prospect that seems likely. “I’m not going out there to try to be Adam LaRoche,” Morse said. “He’s an awesome defensive player.” The early returns have shown he’s not bad, either.