Jon Machota of the Dallas Morning News shared word of the injury Monday, but he noted head coach Jason Garrett said Prescott "was doing well" following the game and on Monday morning.
Losing Prescott for significant time would be a serious blow to Dallas' postseason chances. Last season, he took over for an injured Tony Romo and reached the Pro Bowl as a rookie with 3,667 passing yards, 282 rushing yards and 29 total touchdowns.
He has followed that with 506 passing yards, 48 rushing yards and three touchdowns through two games this year.
Dallas selected Prescott in the fourth round of the 2016 draft after he thrived at Mississippi State, and he led the team to the No. 1 seed in the NFC alongside rookie running back Ezekiel Elliott. While the Cowboys can still rely on Elliott behind a strong offensive line, opposing defenses will likely stack the box if Prescott is out.
Kellen Moore would likely get the nod if Prescott is forced to miss time, although Cooper Rush is another option. Moore entered the 2017 campaign with only three regular-season games on his resume and four touchdown passes to go with six interceptions.
It is difficult to envision the Cowboys winning the Super Bowl with Moore, so Prescott's speedy recovery would be welcome news for the defending NFC East champions.