McBriar's foot was broken Sunday when his punt was blocked by the Cardinals and recovered for the winning touchdown.
The Cowboys signed Sam Paulescu, who was in training camp with Dallas in 2007 and in Denver's camp this year. Paulescu, undrafted out of Oregon State, has punted in only one NFL game, averaging 44.2 yards on five kicks in the Broncos' 2007 season finale.
McBriar won't need surgery but will need up to two months to recover, too long to keep him inactive on the roster. After his foot was hit by an unblocked rusher, McBriar had to be carted off the field.
McBriar, in his fifth season, was a Pro Bowler in 2006, when he had a 48.2-yard average. This season, he punted 24 times for a 49.0 average, second in the NFC and fourth in the NFL.