DETROIT - The Twins won their first two games over the Tigers this week, but each time, they came back the next day with news that they were demoting the previous night's starter to Class AAA Rochester.

Tuesday, they sent rookie Liam Hendriks back down with a 7.04 ERA. Wednesday, Nick Blackburn was sent back to Rochester with his ERA at 8.10.

"Unfortunately, it's what needed to happen with the way things are going," Blackburn said. "I'm not doing the team any good here. Hopefully, I can get down there and get some confidence and do what I know I can do."

After promoting righthanded starter Cole De Vries to replace Hendriks, the Twins promoted righthanded reliever Casey Fien to take Blackburn's roster spot.

Fien, 28, signed a minor league deal with the Twins last winter and posted a 4.30 ERA in 33 games for Rochester, converting nine of his 12 save chances. He was expected to arrive in Detroit late Wednesday and be available to pitch Thursday.

With so much instability in the rotation, the Twins know they will need Blackburn again eventually. They hope this works like July 2010, when he went 2-7 with a 9.88 ERA in nine starts before getting sent to Rochester. After returning, he was 3-4 with a 3.05 ERA in eight starts to finish the season.

This year, Blackburn dealt with shoulder and rib cage issues before landing on the disabled list because of a quadriceps injury in mid-May. Since returning from the DL on June 4, he insists he has been healthy, and he had the 93-miles-per-hour sinker Tuesday to prove it. But he has given up 39 hits and seven home runs in his past 25 innings.

"Even when he makes a good pitch, it seems to find a hole," manager Ron Gardenhire said. "Sinkerballers live with that possibility. When they get ground balls, they have to be at people. Right now, the frustration has set in. If he makes a bad pitch, instead of it popping up, it goes out of the ballpark."

Added Blackburn: "I think the pitches are there, and the mechanics are better, but I just need to get the confidence to be able to go out and execute."

Saturday's starter TBA

Blackburn was scheduled to start Sunday at Texas, but the Twins have decided to give that start to just-recalled righthander Cole De Vries.

De Vries pitched two innings in relief Wednesday, with the Twins looking to give their relievers as much rest as possible. De Vries was scheduled to start Saturday, but Gardenhire said they will have another pitcher make that start instead.

P.J. Walters remains scheduled for a second rehab start for Rochester on Friday, so it won't be him, but 29-year-old righthander Sam Deduno remains a candidate. They would need to add Deduno to the 40-man roster, but even after adding Fien, they still have one open spot.


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