Their bullpen struggling for much of April, Hill's return could not have come at a better time.
Hill stayed on course with his rehab and never had a setback, enabling him to beat the clock and return to the roster for his hometown team, the one he has pitched for since 2010.
"I didn't really know at the time as far as how long it was going to take with the rehab process, but as soon as you start throwing and you start to feel like stuff is coming along and you get into the long-toss part of your program, you know things are going to go pretty smoothly and you kind of stay where you're at at every segment," Hill said. "You don't try to get too far ahead of yourself. You don't try to push the envelope with the rehab process."
To make room for Hill on the roster, the Red Sox optioned lefty Justin Thomas to Triple-A Pawtucket. Thomas posted a 7.71 ERA in seven games.
If the Red Sox can get Hill pitching like he was a year ago, when he didn't allow an earned run while striking out 12 batters over eight innings in nine appearances, they could have a significant weapon.
And one reason for optimism is that Hill feels a lot stronger than he did last season, before the injury.
"I feel like the ball's coming out better. I do. I feel like it's coming out with more life," Hill said. "It just seems like everything is put together better, and that's probably mostly due to the regimen of working out this offseason, again, the rehab part of it. When I say the rehab part of it, I mean the work we did in the training room, the shoulder program we did. I don't really think you're rehabbing the elbow. It's more making sure you maintain and continue to strengthen your shoulder. There's a lot of work that goes into it."
Manager Bobby Valentine was happy to have Hill back in the fold.
"He's worked so hard, stayed with the program, and has been religious with his work ethic," Valentine said. "It's a credit to a plan that was followed and a guy who was able to follow the plan. He's been on the mound 17, 18 times. Eleven of them have been in competition. He's done well. He's, I think, physically ready to be here."
The Red Sox could soon have another lefty reliever back in action in Andrew Miller, who started the season on the disabled list with a left hamstring strain. Miller has pitched eight games in the Minors, posting a 4.32 ERA.
"[General manager] Ben [Cherington] talked to him," Valentine said. "He was talked to when Rich came up. He feels he's close. We feel he's close. [He needs] a little more consistency, but he's throwing well."