DALLAS (Reuters) - Dallas Cowboys quarterback Tony Romo could be sidelined for up to four weeks with a broken finger, his team said Monday.

The Pro Bowler broke the little finger in his throwing hand during the first play of the 30-24 overtime loss to the Arizona Cardinals Sunday, the Cowboys (4-2) said on their website (www.dallascowboys.com).

Romo has started every regular season game since taking over from Drew Bledsoe during the 2006 campaign and completed 128-of-201 pass attempts for 1,689-yards and 14 touchdowns this season.

Brad Johnson, who guided the Tampa Bay Buccaneers to the 2003 Super Bowl during his 15-season career, is expected to take over quarterbacking duties in Romo's absence.

(Writing by Steve Keating in Toronto, editing by Padraic Halpin)