After Brady and Super Bowl champion New England got rolling in a 30-6 victory, Dallas coach Jason Garrett essentially declared the quarterback competition open with Romo missing at least four more games because of a broken left collarbone.
Weeden is 0-3 as Romo's replacement, extending his personal losing streak to 11 starts going back to his days as a first-round pick by the Browns. And Matt Cassel, acquired in a trade with Buffalo after Romo's injury, is ready to play. He was active for the first time against the Patriots.
The Cowboys (2-3) have the bye to consider a switch to Cassel. Their next game is Oct. 25 at the New York Giants.
''I don't really believe in making changes for change sake,'' Garrett said Monday. ''If you just start changing things for the hell of it, everybody starts looking around like, `What are these guys doing?' We have core beliefs. We have convictions about how we want to do things.''
Weeden had 36 yards passing at halftime, and the running game wasn't much help as it continues to struggle without DeMarco Murray, who led the NFL in rushing last season before leaving for Philadelphia in free agency.
The problems for Dallas are compounded by the absence of star receiver Dez Bryant, who could return against the Giants after breaking his right foot in the opener against them. Romo went down the next week.
''The quarterback is one of those positions where you don't isolate him,'' Garrett said. ''His impact on the offense is important. His impact on the football team is important. You put all of those factors together and you try to make your best judgment.''
Cassel started 71 games over seven seasons with New England, Kansas City and Minnesota - nearly three times as many starts as Weeden. He led the Patriots to an 11-5 record after Brady went down with a season-ending knee injury in the 2008 opener, although they missed the playoffs.
The 33-year-old Cassel was inactive for two weeks while learning the Dallas offense, but replaced Kellen Moore as the backup to Weeden against his former team. Moore, in his fourth year, has never played in the regular season.
''He's certainly comfortable enough,'' Garrett said of Cassel. ''We wouldn't have put him in that situation yesterday to be the backup QB with a possibility of going into the game if something were to happen to Brandon.''
It's not the first time Weeden has heard questions whether he should start. He was a frequent target of Cleveland fans while going 5-15 as the starter, even getting booed once as he entered a game for an injured Jason Campbell during the second of his two seasons.
Weeden hasn't won when starting since late in his rookie year in 2012. This is his second season as the backup to Romo. He lost once last year to Arizona when Romo was out with a back injury.
''You can't sit back and rewind on those bad plays,'' Weeden said. ''Obviously we are in a little bit of a rut.''
Terrance Williams, the top threat with Bryant sidelined, was visibly frustrated at Weeden for an overthrow on what would have been a meaningless late touchdown against the Patriots. The third-year receiver downplayed his reaction after the game.
''It's not just him - we're a team,'' Williams said. ''The whole crew is going to ride with him, from the receivers to the coaching staff. I really don't see any ... (need for a) change.''
Williams is about to see if the coaching staff agrees.
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