ST. PETERSBURG, FLA. - Francisco Liriano fell behind hitters, was visited multiple times by catcher Joe Mauer, looked dejected on the mound, fell behind more hitters, gave up runs and lost another game for his team Sunday.

After coming out of spring training looking prepared and mentally calibrated to return to his dominating ways, Liriano has become the most unsure thing in a rotation that entered Sunday with a 6.25 ERA. With Scott Baker out for the season because of elbow surgery, the Twins have needed Liriano more than ever to pitch like a staff ace, and he has failed them.

"We're kind of baffled right now," manager Ron Gardenhire said.

It wasn't a surprise that, after the Twins lost 6-2 to the Rays, Gardenhire hinted at a change in status with Flustered Frankie.

"It doesn't look like he's pitching with a lot of confidence right now," Gardenhire said. "We've said this over and over again so we are going to step back and figure out what we need to do to try to get his confidence back and try to figure some things out with him."

It's not hard to tell that Liriano is not himself and that he's killing the Twins' chances of getting on any kind of roll with their starting pitching.

Liriano knows it, too, and is aware that he could land in the Twins' bullpen after starting 0-3 with a fat 11.02 ERA.

"That would be OK with me," Liriano said. "Like I said, they gave me an opportunity to start and I haven't done my job yet, so, if they think it's going to make me better, I'll do it."

Liriano was decent for two innings Sunday, throwing only 24 pitches. But in the third inning, his pitches got up in the zone. He fell behind Sean Rodriguez -- batting .214 -- and walked him. He fell behind backup catcher Chris Gimenez and walked him. He hit Elliot Johnson -- the No. 9 hitter -- with a pitch, loading the bases. Mauer made three visits to the mound in the inning to try to get Liriano recalibrated. It kinda worked, but Tampa Bay got two sacrifice flies to open the scoring -- and Liriano hadn't given up a hit yet.

"The first couple of innings it looked like it was going to be a pretty good day for him," Mauer said, "and things happened during the course of the game and he just couldn't get back on track."

In five innings, Liriano gave up five runs, three hits and four walks -- including a homer to Desmond Jennings, who said after the game that he's not a home-run hitter.

"I've just got to stay relaxed and try to figure out what I'm doing wrong, work on it and try to get better," Liriano said.

When a manager talks about taking a step back, it means skipping a start, moving to the bullpen or sending a player to the minors. Gardenhire and pitching coach Rick Anderson have a big decision to make. Can Liriano get his mojo back with a bullpen stint? Should he go to Class AAA Rochester? They could swap him for lefthander Scott Diamond, who is 4-0 with a 1.07 ERA after giving up two unearned runs on Sunday.

How convenient that they are starting on the same day. And Diamond is on the 40-man roster. But that's tricky: Liriano, because he has at least five years of experience, has to agree to be sent down.

But assigning him another start could be torture for everyone.

"One good start and your confidence comes right back," Gardenhire said. "We're kind of scuffling along with it . We'll talk to Liriano, we'll talk to Andy and try to figure out what we need to do to help him out."

La Velle E. Neal III • lneal@startribune.com