There's also the possibility that another Red Sox starter could go down to injury. Wakefield is 41-years-old and he's had some struggles with injuries the past two years. Josh Beckett has been healthy the last two years, but he's had injury troubles in the past as well.
Should the Red Sox look to add another starter to the team via trade, Sheets would be an ideal candidate. His availability will likely hinge on how competitive the Brewers are next year. But the Brewers contemplated trading Sheets this offseason. He's the highest paid player on the team, and he will be a free agent after the 2008 season.
Sheets has had large struggles with injury but the risk would be relatively low to bring him in for half a season. It's unlikely that the Brewers will bring him back after he's failed to reach the 160 innings mark in any of the last three seasons. And since there's very little left on his contract, a deal for Sheets likely wouldn't require giving up a lot of talent.
The Red Sox talked to the Brewers about Sheets earlier in the offseason, before news of Schilling's injury. I don't see why they wouldn't return to talks should they need starting help once the season begins. The Red Sox could potentially have a lot of spare parts. Coco Crisp, Julian Tavarez, Jed Lowrie, Justin Masterson, Craig Hansen or Ryan Kalish could be included in a potential deal for the Brewers ace.