Walker (back) won't make his scheduled start Sunday against the Phillies, though he's expected to avoid the injured list and could start Tuesday against the Yankees, Tim Healey of Newsday reports.
Back spasms forced Walker to exit his previous start Tuesday against Atlanta, but the issue doesn't seem like a major one. While he'll need at least a couple extra days to rest, he may not need to miss even one full turn in the rotation. The Mets have yet to announce a starter for Sunday's contest.