Buffalo Bills rookie quarterback Josh Allen will reportedly not start against the Indianapolis Colts on Sunday, "and there is concern he will miss [multiple] weeks," according to ESPN's Dianna Russini.
Allen exited Sunday's 20-13 loss to the Houston Texans with an elbow injury and did not return.
On Monday, ESPN's Adam Schefter and Chris Mortensen reported Allen injured the UCL in his throwing elbow. Although the injury isn't considered major, the Bills will send him for a second opinion.
Schefter noted that Tennessee Titans signal-caller Marcus Mariota missed two starts with a UCL-related injury this season.
Buffalo selected Allen with the No. 7 overall pick in the 2018 NFL draft out of Wyoming knowing he would be a project.
Allen was thrust into action during the first game of the season, however, after starter Nathan Peterman struggled.
While Allen has gone a respectable 2-3 as a starter and flashed his enormous potential at times, he has also taken his lumps behind a suspect offensive line and without the benefit of elite weapons around him.
The 22-year-old is completing 54 percent of his passes for 832 yards with two touchdowns and five interceptions, while rushing for 155 yards and three scores.
Most impressively, Allen led the Bills to an upset road win over the Minnesota Vikings in Week 3.
Peterman replaced Allen on Sunday, but after throwing a go-ahead touchdown pass, things went downhill for the 2017 fifth-round pick.
He threw a pick-six to Texans cornerback Jonathan Joseph with just 1:23 remaining in the fourth quarter, which gave Houston a 20-13 lead.
The Bills got the ball back, but Peterman then threw a game-ending interception to Kareem Jackson.
In six career regular-season appearances, Peterman has thrown for 337 yards with three touchdowns and nine interceptions.
He infamously threw five picks in his first career start against the Los Angeles Chargers last season, and he has thrown four picks in two games this season.
Buffalo's only other option at quarterback is veteran Derek Anderson, who signed with the team last week.
While Anderson hasn't been with the Bills long, he is familiar with McDermott and general manager Brandon Beane from their time together with the Carolina Panthers.
Also, Bills offensive coordinator Brian Daboll was the Cleveland Browns offensive coordinator when Anderson was with the team in 2009.
Given those factors and Peterman's poor play, Anderson may be Buffalo's best bet under center against the Colts if Allen can't go.