"I watched him hit in the cage and he looked real good," Stoneman said. "He looks better than I've ever seen him. Physically, he looks real good. Obviously, he's been able to do a lot of upper body work (in the weight room). Now it's a matter of getting the leg back to where it was before the injury."
Though the Angels still refuse to put a timetable on his return, Stoneman admitted it is "a possibility" that Rivera will be ready to start a minor-league injury-rehabilitation assignment within the next couple weeks. That could put him on pace to return before the end of August.
"That would give us a big lift if Juan can get back to doing the things we know he can do," Angels manager Mike Scioscia said. "I think it's realistic. But it's not like anyone has a crystal ball to see (how much he will be able to contribute). There are some challenges he has first to get healthy, to get into baseball shape and then get productive."
Rivera hit .310 with 23 home runs and 85 RBIs in 124 games last season.
Mike Napoli went through a defensive workout Saturday and Sunday and should be ready to come off the disabled list this week. Napoli has been sidelined with a deep bruise in his left shin since a game-ending play at the plate on July 1 at Baltimore.