"I'm excited to just get back and do my part and be part of the team again," said Hardy, who hit .200 with three doubles and two RBIs in six games before the injury -- yet marked his comeback by reaching safely five times in six plate appearances.
Hardy, who went 2-for-9 with three walks in three rehab games at Triple-A Norfolk, said the biggest test was how his body felt on Saturday morning.
"That first game, I was real worried, but coming in the next day and feeling basically 100 percent gave me a lot of confidence," Hardy said. "I pretty much did everything in the first game I played; I reached about as far as I could for a ball [and] didn't feel anything, so that's a good thing. I was swinging basically 100 percent; I slid into home one night ... so there shouldn't be any doubt or worry."
Orioles manager Buck Showalter, who saw videotape of Hardy's performance, was equally assured that the shortstop is ready.
"We feel confident as you can be that physically he's ready, baseball-wise," Showalter said of Hardy, who was in Tuesday's starting lineup. "I called J.J. last because I knew what he was going to tell me. He would have said that he's ready to go Sunday."
Hardy, who was placed on the DL on April 13, retroactive to April 10, said he feels his timing at the plate is close to regular-season form and wasn't worried about having to start from scratch.
"I felt like I got quite a few [at-bats] in spring, and once you do that, it doesn't take as long to get it back," Hardy said of his swing. "If I'm not [completely] there, I feel like I'm close. It shouldn't be too long."
To make room for Hardy on the 25-man roster, the Orioles designated right-hander Josh Rupe for assignment, and the O's are optimistic that if he clears, he can pitch in Triple-A Norfolk as soon as Friday.
"For his sake, if he gets claimed, I'll feel good for him there, too," Showalter said of Rupe, who pitched to a 5.65 ERA (nine earned runs in 14 1/3 innings) in nine outings.
"We just needed to get to 12 pitchers with J.J. coming back and we felt like, basically, of all the options available for us right now, that was a better fit. ... If we use up the bullpen, then we have avenues to go -- one of which will be him, if he clears."
Jason Berken as the lone long reliever in the bullpen, and the decision to designate Rupe, instead of a one-inning pitcher like Clay Rapada, comes down to roster management. Given that Rapada's niche as a lefty specialist is more in demand, he would have likely been claimed by another team on the waiver wire.
Showalter said the team has a contingency plan if the short outings from their starters continue, a plan that would likely involve recalling another fresh arm from Triple-A in exchange for one of the team's starters.
"I don't think you will see one of our starters go in the bullpen right now," Showalter said. "But that's an option that has presented [itself]. And if [president of baseball operations Andy MacPhail] feels strongly about it, we might do it. But I'd rather them pitch well and we don't have to worry about it. But we'll see."