Thielbar was signed by the Twins out of the independent Northern League in 2011 and raced through High-A and AA up to AAA-Rochester in 2012. He began this year fairly slowly, but, most recently, has had eight straight outings without an earned run. His overall numbers include more strikeouts (34) than innings pitched (26.1) and good control (just 8 BB). (For more on Thielbar, check out his "Adopt-A-Prospect" page on Twins Daily.)
The Twins travel to Atlanta this week, a National League city, where they will be unable to use a designated hitter. American League teams often like to add a bullpen arm for such trips. With Hernandez's demotion, the Twins are shorting themselves a fifth starter until Friday, when they next need one. If that's the case, Theilbar's promotion to the big leagues could be short-lived.
For Friday's start, the assumption is that Kyle Gibson would be first in line to join the Twins rotation. Gibson, a first-round draft choice who missed most of 2012 coming back from Tommy John surgery, has thrown two complete game shutouts in his last three outings. Gibson is also on the 40-man roster. The only other AAA starter on the 40-man is Cole DeVries, who is also just coming back from an injury. He too pitched on Sunday, so his next turn in the rotation could also fall on Friday.
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