Nava played 69 games in RF this past season and we did okay. He played more innings in RF last year than he did in LF.
It's not like we're in trouble if he has to play 15 games in right while someone goes on the DL.
Fielding Bible has Nava as about an average OF last year (which is surprising, especially considering he played a lot of LF in Fenway, where their numbers aren't adjusted enough for the Wall IMO.)
In LF last year they have him as -1 in 469 innings. In RF they have him as -3 last year in 493 innings and +1 in 2012 in only 20.1 innings. He's not as bad as everyone seems to fear.
I don't think we're going to be using a roster spot on a backup CF this year, at least not at the start. But we really need a decent guy in AAA who can come up and play the position. Right now, we really don't have anyone in that spot. Hazelbaker's gone, Linares got dropped to AA last year, Brentz and Hassan are corner OFs.
Sox Prospects has an organizational depth chart, and we look really solidly deep everywhere on the field except CF and SS.
We can't go into the season with Shannon Wilkerson as the #2 CF on the depth chart (he's behind Victorino there too obviously, but right now he is the presumptive starter in Pawtucket.) Wilkerson's going to be 26 this year and the highest OBP he's ever managed in the pros is .322 in A ball. We don't want to see him playing for the Red Sox this year and frankly I don't even want him to be the regular CF for Pawtucket.
We need someone who will start the year as Pawtucket's CF who can ride the shuttle and has a chance of not being terrible if he played for the big club for a couple weeks. (The Yankees added a guy like that with a minor league deal to
Antoan Richardson, who will never be a regular in the majors but who could be useful when stashed at AAA.)
Similar deal at SS, where Marrero will only be starting AA ball this year. In that spot, we should carry someone on the 25-man who can play SS for a couple weeks if Bogaerts or Middlebrooks is hurt or playing badly for a long time. A guy like that who is primarily a SS (and who can play solid defense there) gives you depth for both positions. I think
Munenori Kawasaki would be a decent choice for that spot. He would cost virtually nothing to acquire (might even take a minor league deal) plays about a league average SS defensively, can play 2B, gets on base decently for a SS (.326 OBP last year) can run a little bit. Solid utility IF who can play SS for a couple weeks if needed and not kill us.
I'm fine with shooting higher than that, but it's got to be a guy who can play solid SS defensively for that role IMO. There aren't many around who aren't terrible with the bat.