Fossum pitched carefully to the fourth batter he faced, walking Gary Sheffield on four pitches, before retiring Marcus Thames on a flyout to end the inning.
Afterward he seemed pleased with his outing.
"It just happened so fast, I can barely remember it," Fossum said. "The important thing is that I felt really good and I had some good break in my breaking balls. It's just a matter of dialing in in a game situation. The more and more I get out there, I'll be more relaxed and able to get into a good rhythm."
Fossum faced a quality Major League lineup from the Tigers.
"That's a pretty good lineup to see your first time back," Fossum said. "But it's good. It tells me where I am right now. I felt pretty good about it. ... I'm looking forward to my next [outing]. And hopefully tomorrow will be fine."
"Tomorrow" is an important aspect for Fossum at this juncture.
"Of course you want to feel good in the game, but you want to be able to wake up and lift your arm up," Fossum said. "The big thing with any kind of surgery and rehab is recovery. Am I going to be able to make my next start? I've thrown more pitches than [I threw Monday] during my [bullpen sessions], and I've been recovering well. So I don't see any reason why I shouldn't be like that tomorrow."
Cuts coming: The first roster cuts of the spring are looming.
"We're going to have a meeting tonight," Rays manager Joe Maddon said. "We're cutting very soon."
Maddon hasn't decided whether news of the cuts will be delivered before or after practice.
"I know last year some of the guys were kind of concerned about that stuff," Maddon said. "For me, we just have to pick the right time of the day to do it. There's never really any good time, or better time, we just have to fit it in our schedule and determine when's a better time to do it. I haven't decided that yet."
Maddon doesn't believe any of those being cut will be surprised to be heading down to Minor League camp.
"You still need to keep 'X' number of guys around to play in these games," Maddon said. "There is no exact number, but just going over the names there seems to be some obvious choices of guys who need to move along to play on a more consistent basis for their own benefit, too."
Battle brewing: A battle is brewing between B.J. Upton and Brendan Harris for the team's utility infielder slot.
"Oh, it's a great battle, my God, it's awesome," Maddon said. "B.J. is starting to settle in. His performance is really coming up. ... And Brendan, he just goes about his business. He's a bulldog. And I love the way he goes about it."
Maddon said he has been pleasantly surprised at the polish Harris has shown.
"I had talked to different people in the offseason about him when we acquired him, and I heard different things," Maddon said. "And then I got to see him on the field. He's more accomplished than I've been told, I'll say that. They spoke about his character and work ethic, but I didn't even realize how good they were. ... He's actually more than what I'd been told."
And for the tough question: Can Harris and Upton both make the team?
"I don't know," Maddon said. "I think anything is possible -- it is possible. And that would be something we'd have to determine toward the end, obviously. It's not impossible."
This and that: Dioner Navarro's sore hamstring is improving and he's expected to be playing again by the end of the week. ... Seth McClung has struggled with his fastball command, prompting Maddon to note that until the right-hander improves in that area, he can't be considered the closer. "By no means has that role been established for him," Maddon said.
Up next: The Rays will host the Phillies at Progress Energy Park in a 1:05 p.m. ET contest on Tuesday. Left-hander Scott Kazmir will make his third start of the spring after experiencing two rough outings against the Blue Jays and Pirates. Right-handers Tim Corcoran, Dan Miceli and Juan Salas will also pitch for the Rays. Righty Adam Eaton is scheduled to start for the Phillies.