Ryan Mountcastle, the former first-round draft pick and a top Orioles hitting prospect who hasn't found a defensive home yet on the diamond, is adding another position to his repertoire at major league camp.Mountcastle, who turned 22 on Monday, worked primarily at first base during the first full-team workout at Orioles camp after just one full season at third base, with the Orioles' new coaching staff giving him his third position since he was drafted in 2015 as a shortstop in hopes of finding an easier path for his advanced bat to reach the majors.While Mountcastle hasn't had his introductory sit-down meeting with the coaches and front office yet after arriving this weekend at his second major league camp, he said Monday after the team's workout that it's "not permanent," but that third base coach José Flores told him upon his arrival that they wanted him to get used to the position."It was just trying to get me to play more positions," Mountcastle said. "Flores had me working there the last few days, just trying to get comfortable with it so whenever they need me out there at first, they can put me out there and feel confident."Without referring to anyone specifically, manager Brandon Hyde said that it was fair to assume that players were in their primary positions Monday for the first day of workouts.Though Trey Mancini worked at first base during Sunday's workout, he was with the outfielders Monday, leaving only Chris Davis and Mountcastle to rotate through infield drills on the Earl Weaver Little Field on the first full-squad day. Mark Trumbo also represents a piece of major league first-base depth, but he's working his way back from offseason knee surgery.Considering this Orioles camp roster doesn't include the low-cost sluggers who were nominally first basemen that previous editions had, Mountcastle's transition might be just as much out of necessity for him as the team."I feel good over there," Mountcastle said. "I got some extra work in today, working on some picks and footwork, stuff like that. I feel good. It's picking up pretty easily, I think."Unlike his last transition, which came midway through his breakout 2017 season in the Orioles' farm system, this one comes at a time when he has several weeks to prepare outside of games.Mountcastle hit .314 with an .885 OPS in his age-20 season at High-A Frederick in 2017 with a minors-leading 51 extra-base hits at the time of his promotion to Double-A Bowie, and that's when the front office decided that his jump in level should also include a move away from shortstop, a position he struggled with because of some throwing issues.Third base presented similar challenges and Mountcastle struggled in his introduction to Bowie, but he rebounded in his first full season there by batting .297 with 13 home runs and 19 doubles in 2018. He enters this season as the Orioles' No. 3 prospect, according to Baseball America.Much of the acclaim that surrounds him, however, is because of his bat. A move to first base would put him in a crowded major league conversation that already includes Davis, Trumbo and Mancini, with the latter two possibly set for more time at first base and designated hitter as the team tries to accommodate the waves of young outfielders on the horizon.If Mountcastle can develop at first, it would alleviate a concern that wasn't big enough to keep him off every major top-100 prospect list this offseason but still raised some red flags with the Orioles' previous regime, who admired his work ethic and the effort he put into improving defensively but didn't make life easy for him by keeping him on the left side of the infield.He never carried his defensive struggles to the plate, though, and a smooth transition to first base could be the last piece of his developmental puzzle."You always want to be comfortable out there, and whether they put me at first or third, I'm going to train my hardest to feel comfortable wherever I'm at," Mountcastle said.