The New England Patriots flew free agent quarterbacks Chris Simms and Tim Rattay to Boston today, with the expectation that they would work out and possibly fill a spot on the team’s suddenly thin quarterback depth chart.

But Adam Schefter of NFL Network reports that when Simms and Rattay arrived, they were told “the situation had changed” and they no longer were needed. So they left without a workout.

It’s not quite clear what the Patriots meant by “the situation had changed.” Tom Brady is still done for the season, and that means the Patriots could still use another quarterback.

So maybe the Patriots plan to sign another free agent quarterback. Chris Mortensen suggested on ESPN’s Monday Night Countdown that Randy Moss might have recommended Daunte Culpepper. And Vinny Testaverde is available. Or maybe the Patriots are working on a trade.

Whatever the Patriots are working on, Matt Cassel is the starter, and he won’t be backed up by Simms or Rattay.