Carp returned in late July and appeared to finally be finding his stroke, hitting .267 in 17 games before straining his left groin muscle while making a stretch at first base. The Mariners brought him back as a September callup, but he got just five starts and 26 at-bats the remainder of the way.
Thus, a season of promise instead produced just a .213 average with five home runs and 20 RBIs in 59 games, despite opening eyes in his first full year by batting .276 with 12 home runs and 46 RBIs in 79 games after a midseason arrival.
"It's unfortunate for Michael," general manager Jack Zduriencik said. "He got hurt right off the bat, then he was up and down [from Triple-A Tacoma]. When you're having those physical issues and then trying to catch up, guys put more pressure and don't get in a groove.
"In Michael's case, probably all those things added in. He got hurt, then he was trying to make up time and it's tough to catch up at the big-league level."
So what now for Carp? The California native has returned to his offseason home near Anaheim to be with his girlfriend and 3-month-old daughter. And after a quick break from baseball, he's beginning the same kind of workout routine that helped transform his career in 2011.
"I've been around long enough now at the higher levels that I know what it takes to play and what it takes to succeed," Carp said before departing Seattle at the end of the season. "I just want to continue building off what I've been doing the last couple years, and obviously get better and let the body heal a little better.
"I'll just focus on getting stronger and coming back and hopefully getting 500-600 at-bats. That's the overall goal. That's what I want more than anything, to have a full season of at-bats. Unfortunately, I haven't had that opportunity yet, but it's going to happen and I know I'm going to hit and it's going to be fun."
Carp feels he just needs a chance -- like the one he got in the second half of 2011 -- to show he's capable of being a productive Major League hitter. To do that, he needs a position, and the Mariners made him a left fielder last year in the hope of adding his power bat to one of their corner outfield spots.
He's more of a natural first baseman, but Carp made enough strides in left field that he surely would have received considerable playing time on a team in need of punch ... if he'd just stayed healthy.
But once Carp's shoulder was hurt and his initial comeback stalled, the Mariners limited him to first base in order to let the arm recover. He's still in that process, but he had already begun getting his throwing strength back in the final weeks of the regular season.
"I'll continue to rehab that," Carp said. "I felt great [toward the end of the season]. It was just a tough go. It was hard to play because there was a roster full of guys."
With first baseman Justin Smoak showing signs of life, he got the bulk of the playing time in September, while Carp mostly watched.
It wasn't an easy situation for a guy burning to get his chance and planning to be a big part of the Mariners' turnaround. But he went about his business quietly and he plans to make whatever he can from what seemed a largely lost year.
"It's a part of the game," Carp said. "Each year you learn something different. You never learn too much in this game. You never know enough.
"I think this was more of a mental year for me. I had to sit back and watch instead of playing. You learn the ins and outs of why this or that happens, and it's just been a unique season."
Unique, of course, refers to something that happens just once. And that is exactly what Carp hopes of his frustrating 2012.
"I'm glad I got that behind me and all I can do is prepare myself to play every day, whatever [position] that will be," Carp said. "I know I'm going to come back. I know I can hit. I always have and hopefully I always will for a long time. I just need to get ready to go and come back and have a strong season next year and help this club out."
And if he does, Carp could once again be a breakout player for a team now searching again this offseason for a corner outfielder to provide just the kind of production he offered in the second half of 2011.