Phillips has begun working out at first base, Jason Mastrodonato of the Boston Herald reports. "We're going to see how versatile we can make this guy," manager Alex Cora said.
The 37-year-old Phillips has played nearly his entire 17-year career as a second baseman and has never played first base. The Red Sox are using a tandem of Mitch Moreland and Steve Pearce at first, but Moreland has slumped since the All-Star break (.183 BA, .594 OPS) while battling various injuries. Phillips made a splash in his Boston debut Wednesday, when he hit a game-winning, two-run homer in the ninth inning against Atlanta.