Twins trying to halt revolving-door rotation

There were already going to be plenty of question marks surrounding the Minnesota Twins’ rotation for the 2013 season. For a while, Nick Blackburn didn’t appear to be one of the question marks.

But the Twins outrighted Blackburn to Triple-A Rochester on Monday, which changes at least his immediate future with the club. Outrighting a player is different than optioning a player to the minors. By being outrighted, Blackburn is no longer on the team’s 40-man roster — a sign that the club is prepared to move in a different direction.

When a player is outrighted, he must first clear waivers before the major league team can assign him to the minors. That means 29 other teams passed on Blackburn, who was 4-9 with a 7.39 ERA in 19 starts with Minnesota this season.

With Blackburn off the 40-man roster at this point in the season, it’s highly unlikely he’ll be put back on it in order to be a September call-up in a week and a half. So how does Blackburn factor into Minnesota’s rotation in 2013? Earlier this month, Twins general manager Terry Ryan said Blackburn would be “in the mix” next year but will have to earn a spot in the rotation.

“There are days that there’d be no question … when you watch him that, ‘OK, he might string one together here,'” Ryan said earlier this month. “Obviously there are other times that things have not gone well. But he’ll be in the mix.”

That fact became even more evident after Monday. Blackburn will be in the final year of his contract in 2013, when he’ll make $5.5 million. The Twins have an $8 million club option on Blackburn for 2014, but it appears unlikely that option will get picked up.

So a look at Minnesota’s current rotation will yield a much different picture than what the Twins broke camp with this spring. None of Minnesota’s five current starters were in the rotation to start the season. Left-hander Francisco Liriano was traded to Chicago. Jason Marquis is also gone after a brief and unsuccessful stint with the Twins; he’s now with San Diego after Minnesota released him in late May.

Veteran right-hander Carl Pavano has been on the disabled list since June 4. Scott Baker has missed the entire season after having Tommy John surgery. Liam Hendriks — whose 2012 season was briefly delayed due to food poisoning — has spent much of the year with Rochester.

Three of Minnesota’s five current starters — Samuel Deduno, Scott Diamond and Cole De Vries — began the year in the minors. Left-hander Brian Duensing, who started Monday against Oakland, was in the bullpen to begin the season. Whoever is called up to take Blackburn’s spot in the rotation (possibly Hendriks) will be yet another pitcher who has spent most of the year in the minors.

As a result of the inconsistency, Minnesota’s starting rotation has posted the worst ERA in the American League (5.47) prior to Monday. Only Colorado’s starters have a worse ERA (6.22).

There’s a chance the Twins could see right-hander P.J. Walters return this season. Walters has been on the disabled list a right shoulder injury, but made a rehab start Sunday for Rochester. In that start, Walters pitched three scoreless innings with six strikeouts — an encouraging sign for a Twins team needing any positive pitching news it can get.

Minnesota doesn’t have a ton to play for in the final month and a half of the season, but it will serve as an audition of sorts for several Twins pitchers. It appears Blackburn, entering the final year of a four-year, $14 million deal, will be among the cast of pitchers waiting in line for an audition.

Only time will tell if he can land the role.

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