The Lions may have just lost one half of their two-headed running back monster for the rest of the season.David Montgomery suffered a torn MCL during Detroit’s home loss to the Bills on Sunday, according to NFL Network, and though he will undergo further testing, there is fear that the injury is season-ending.The 27-year-old was held to five carries for 4 yards and four catches for 31 yards on Sunday.The injury is a major blow for a Lions team that is averaging the most points per game (32.8) in the NFL.Two months ago, the Lions rewarded Montgomery with a two-year, $18.25 million contract extension after he helped form a dominant backfield duo with Jahmyr Gibbs.Montgomery, after four seasons with the Bears, initially signed with the Lions in 2023 on a three-year, $18 million contract.In 14 games last season, he had 1,015 yards rushing with 13 touchdowns, adding 183 yards and two touchdowns in three playoff games.Through 14 games this season, Montgomery has 775 yards rushing with 12 touchdowns, along with 36 catches for 341 yards receiving.His injury should lead to a fuller workload for Gibbs, who as a rookie last year earned Pro Bowl honors by rushing for 945 yards and 10 touchdowns, adding 52 catches for 316 yards and a receiving touchdown in 15 games.Gibbs, 22, has 1,047 yards rushing, 395 yards receiving and 14 total touchdowns in 14 games this season.Third-stringer Craig Reynolds is also likely to slide into a more prominent backup role.The Lions (12-2) remain atop the NFC after having their 11-game winning streak snapped on Sunday.They currently own a tiebreaker for the top seed over the Eagles, who improved to 12-2 by defeating the Steelers on Sunday for their 10th consecutive victory....