Joe Nathan left camp in Florida to return to Minneapolis for some tests on his elbow. Undoubtedly at this point, all Joe Nathan owners have large, red sirens going off around them. Elbow problems? Never a good thing. Now, he has had surgery to remove bone spurs during the offseason, and this could be a slight residual effect related to it.
Anyone who already owns Nathan should probably be at least doing some research related to who they would go get should Nathan miss significant time. Let's take a look at the candidates:
Matt Guerrier - In terms of a closer, Guerrier could potentially see some problems. Closers generally are known to need a pretty good strikeout rate, as they will need the occasional strikeout to close out a tough save. But Guerrier is not really well known as a strikeout pitcher, mostly due to his rates. In his last 3 seasons, Guerrier has struck out 6.95, 6.96, and 5.54 per 9 innings. Not exactly a dominating number. I could see him used from time to time depending on matchups, but I don't think that manager Ron Gardenhire will move Guerrier out of the role he is currently slotted for.
Jose Mijares - I like the theory that Mijares could get the opportunity to close. His strikeout rate was solid (8.03 per 9 in 2009). However, his walk rate would need to improve (3.36 per 9 innings) for him to be effective long-term.
Jon Rauch - This seems to be the most likely player to get save chances without Nathan around. Rauch has closed before (both with the Nationals and the Diamondbacks), and prior to 2009 consistently posted a strikeout rate greater than 9.
Jesse Crain - Crain also posted high strikeout rates (7.49 in 2009), but also walked too many (4.70 in 2009). I don't think he's likely to get more than a couple of random save opportunities.
Pat Neshek - Neshek is coming back after having missed the majority of 2009 with an injury. However, when healthy he did post excellent strikeout rates. Not sure I believe in him getting a lot of opportunities either, although there's potential there.
For me, the key is how the pitcher is going to do for you if he doesn't immediately provide saves. Out of this group, I would be inclined to go after Rauch. He has the "I've closed before at some point" seal of approval, and still provides solid peripheral stats in the other categories. But either way, I wouldn't go get any of them quite yet, but you'll have to be vigilant to see when news hits about Nathan's tests.