Bonser Looks to Go Under the Knife

The Minnesota Twins used all of seven starters during the 2008 season, the fewest number in the Major Leagues along with the Phillies and Angels. It looks like two of those seven are now gone as Livan Hernandez is signed with the Mets and news today comes out that Boof Bonser is still experiencing pain and is now set to undergo exploratory surgery on his throwing shoulder.

That type of surgery is rarely good news and it seems likely to expect Bonser to miss most of, if not all of, the 2009 season. On the surface, that would not seem to be that big of a deal, as Bonser was not favored to be in the Twins rotation breaking camp. Scott Baker, Francisco Liriano, Kevin Slowey, Nick Blackburn and Glen Perkins are the oft-reported rotation.

The top four is fine, but supporters of Perkins and detractors of Bonser are ignoring the effects of BABIP and batted ball profiles; Bonser’s FIP (4.19) being almost a full point lower than Perkins’ (5.14). Bonser was better than Perkins in 2008 and projected better than him in 2009, no matter the Twins reluctance to acknowledge that fact.

The loss of Bonser not only spells a loss of opportunity to upgrade from Perkins at the back end of the rotation, but also the loss of depth in the rotation. It is rare, as you may have noted above, for teams to avoid using a number of starters beyond their original five. No matter which of the two ended up outside of the rotation, the presence of both helped to assure the Twins of some insurance in case parts of their young rotation falters.

In what looks like a possibly tight AL Central, these young starting pitchers are the Twins biggest competitive advantage, and a blow to that, is a blow to their overall playoff chances. Hopefully, for them, Bonser’s surgery does not reveal any structural damage.




Print This Post



Matthew Carruth is a software engineer who has been fascinated with baseball statistics since age five. When not dissecting baseball, he is watching hockey or playing soccer.


One Response to “Bonser Looks to Go Under the Knife”

You can follow any responses to this entry through the RSS 2.0 feed.
  1. thrylos98 says:

    I would not think that the situation is quite as dire as projected :)

    first of all, Bonser is getting an exploratory arthroscopic procedure done on his shoulder to figure out where the pain comes from because MRIs and X-rays cannot find anything. The good news with this is that there is probably no ligament or muscle damage (or even inflammation because a cortisone shot was ineffective) or bone spurs (those would have popped out in those exams). In decreasing severity, it could be scar tissue (that can be scraped by the scope), fluid build up, something funky, or good old arthritis (that’s a bad thing; career ending.) That said, scopes are practically a weekly occurrence in football locker rooms and players who undergo such a procedure usually are back on the field within a week or two.

    Regarding how bad a blow this could be for the Twins. Perkins with all his inadequacies is ok for a 5th starter and projects to something like 1.9 wins above replacement. Bonser has great stuff and this would be the season that he would officially make an 100% transition to the pen and fight fot the set up job. In the organization’s mind he is not a starter any more. Even in the worse case scenario that Bonser would be unavailable for this season, his 0.6-0.7 WAR in the pen would be easily replaced by Ayala, esp. if he rebounds.

    Duensing, Swarzak, Mulvey (even Humber) are waiting in the wings if Perkins falters. In the big schema of things this is not a big deal for this season.

    Vote -1 Vote +1

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>