Sandy Alderson just gave a quick update at spring training regarding injuries, and, unfortunately, Johan Santana's first spring training start has been pushed back from March 2 to the middle of the month. Alderson says it's nothing structural, but this news certainly isn't good for the Mets.
Santana, of course, missed all of the 2011 season and only threw 117 innings last year because of major shoulder surgery on his pitching arm. If he is, indeed, just in need of extra time to ramp up to regular season form, that's not the end of the world, but it's easy to imagine something bigger is at play here.
If Santana doesn't end up starting the season in the team's rotation — speculation at this point — it'd probably be mighty tempting for the organization to put Zack Wheeler in his place to begin the year if he has a good spring. But other pitchers who have already debuted in the big leagues would make more sense, as an April start to Wheeler's big league career would ultimately cost the Mets a year of team control. It wouldn't be worth it for four weeks of Wheeler.