As the Twins weigh whether to trade Kevin Slowey for bullpen help, they have new concerns about their starting pitching depth.

Aside from Scott Baker's recent trip to the disabled list with a sore elbow, their starting rotation has been healthy all season, but the Twins know how fast that can change. Last year, they used nine starting pitchers.

Anthony Swarzak has proven capable in four spot starts, posting a 3.16 ERA. Scott Diamond also had a decent spot start in last Monday's doubleheader against Cleveland.

But Slowey is their only other bona fide option at Class AAA Rochester. There was a thought that top prospect Kyle Gibson would be ready by now, but the 2009 first-round draft pick is showing signs of fatigue at Rochester, and is 3-8 with a 4.81 ERA.

On Friday, Gibson threw just 47 of his 94 pitches for strikes in Indianapolis, walking five and striking out one in five innings.

Gibson, 23, leads the Red Wings with 95 1/3 innings pitched after throwing 152 last year on his climb from Class A to AAA. The Twins had Gibson rest from June 30 to July 17, and there is talk now of curtailing his innings again, with insiders doubting that he will pitch in the majors this year.

Orioles a possible fit? The Orioles appear willing to move righthanded reliever Koji Uehara, who entered Saturday with a 1.84 ERA and 58 strikeouts in 44 innings pitched.

Bob Hegman, who normally scouts the AL Central and NL Central for the Twins, was at Camden Yards on Saturday watching the Orioles and Angels. Meanwhile, Orioles scout Lee MacPhail has been at Target Field the past few days.

The teams showed their ability to make a deal last winter, when the Twins sent shortstop J.J. Hardy to Baltimore for minor league pitchers Jim Hoey and Brett Jacobson.

Slowey might be a fit in Baltimore. Uehara, 36, is making $3 million this year and has a $4 million option for next year that will kick in automatically with 15 more appearances.

Revere, Nishioka don't sit Twins manager Ron Gardenhire acknowledged that Ben Revere and Tsuyoshi Nishioka could both use a rest but kept them in the lineup anyway Saturday.

Revere was in a 1-for-25 skid but walked to lead off the first inning, scoring on Michael Cuddyer's two-out single. Revere lined a single in third inning before grounding into double plays in his final two at-bats in the Twins' 4-1 victory over the Tigers.

"The heat's been unbelievable, and he's playing every day," Gardenhire said. "I think he needs a break right now, but this is not the time."

Nishioka was hitless in the first two games of the Detroit series before going 2-for-3 with two singles Saturday.

"Nishi's also in a situation where there's not many options [on the bench]," Gardenhire said. "There's just no breaks right now. He's a little beat up, probably could use a day off, but he's just going to have to play."

Liriano's next test Francisco Liriano will make his third start on this 12-game homestand Sunday when the Twins and Tigers wrap up their four-game series.

Liriano went 1-0 with a 1.38 ERA in those first two starts, defeating the Royals on July 14 and taking a no-decision against Cleveland on Tuesday, despite giving up only one run over six innings in a game the Twins won 2-1.

"To me [Sunday's] just another game for me," Liriano said. "Go out there and try not to do too much."