Barring trade or injury, the Twins rotation for 2009 seems pretty much settled. Baker, Liriano, Slowey, Blackburn and Perkins have all earned return engagements. Its hard to imagine any of them losing their spot in the rotation based on spring training performances, either by them or by any potential replacements. I don't recall the last time the Twins had a rotation settled from one through five for the following season. There may not have been a last time because it has never happened before.
Does that mean the Twins will have an outstanding rotation next year? No. They really lack a dominating ace. Baker is getting that buzz now, but he is really just the most dependable of the bunch. Liriano certainly has the talent and with another year into his recovery could take that spot. Slowey is a solid number three starter and Blackburn and Perkins both fill out the rotation. Its possible this crew will develop into a dominating rotation with another year of experience. Its also possible one of them will fall flat on their face next year. But at this point there is not much to do but watch with anticipation as it plays itself out next year