For Bonser, the callup is his first taste of Major League ball, and it is also a well deserved one. So far this season, Bonser was third in the International League in earned run average (2.01), and strikeouts (47), and had lead Rochester to one of the best team-ERAs in the International League.
Bonser came over to the Twins in the A.J. Pierzynski trade, which seems to just get more and more lopsided. With Bonser, the Twins also acquired Joe Nathan and Francisco Liriano, and now the three of them will be a focal point in the Twins' success this season. Liriano is already in the Twins' rotation, and Nathan is one of the best closers in the American League.
The Twins will now go with three starters in the rotation, with Scott Baker joining Liriano and Bonser. They also have Willie Eyre as one of their best bullpen guys, and Eyre is also in his first season in the Major Leagues. These kids will have to grow up fast if the Twins want to compete in the American League Central this season.
The fact that the AL Central is so good this season is one reason why the Twins could not wait for Lohse to get his act together. The Detroit Tigers are one of the best teams in baseball this year, and the White Sox are the White Sox, so it was imperative that the Twins make a move quickly.
As for Lohse, he is going to the Minors to get his act together. If it was just a mechanical thing, then the Twins would have moved him to the bullpen, but this is something different. He has not seemed like the same pitcher, and he can use this demotion to either make or break him as a pitcher.