TAMPA, Fla. — No Tom Brady equals little offense for the New England Patriots, though it's difficult to gauge how much that concerns coach Bill Belichick at this stage of the preseason.

With the 2007 MVP sitting out for the second straight week, the defending AFC champions sputtered with backup Matt Cassel running the show in a 27-10 loss to the Tampa Bay Buccaneers on Sunday night.

"I think it was pretty obvious we've got a lot of work to do, based on tonight, in all three phases of the game," said Belichick, who played down the significance of Brady not playing.

Brady remained at home, reportedly to rest a sore foot, and Cassel had limited success moving the ball against a feisty Bucs defense that scored on his third-quarter fumble and intercepted the first pass thrown by successor, Kevin O'Connell.

Asked if Brady would have played had it been a regular-season game, Belichick said: "Well, it's not a regular-season game."

And, would he characterize Brady's not playing as precautionary? "I wouldn't characterize it," he replied.

Bucs starting quarterback Jeff Garcia also has yet to play this preseason after missing most of training camp with a sprained right calf. His absence is creating plenty of opportunities for Brian Griese, Luke McCown and Chris Simms to build their cases for being No. 2.

Griese and McCown produced a 17-3 halftime lead, with the Patriots scoring on Stephen Gostkowski's 53-yard field goal on the final play of the second quarter.

Blitzing safety Sabby Piscitelli scooped up an errant shotgun snap to Cassel and ran 24 yards for a touchdown that made 24-3 early in the third.

Griese, listed third on the depth chart, got the start and directed an impressive 17-play, 80-yard TD drive on the first possession of the night.