Baltimore Ravens cornerback Lardarius Webb tore his ACL Sunday during the Ravens game against the Dallas Cowboys on Sunday, according to a report from ESPN's Adam Schefter.

Webb, the Ravens top cornerback, will likely be headed for injured reserve and will miss the rest of the season. He suffered the injury while attempting to cover Cowboys wide receiver Dez Bryant. Webb fell to the turf clutching his knee before being helped off the field. The injury was initially thought to be a sprain, but later examination revealed the torn ACL.

The injury will be a major blow for the Ravens defense as Webb was widely regarded as their best cover corner. Baltimore signed Webb to a six-year $52.74 million contract extension prior to the season. Without Webb, Baltimore will now likely rely on former first-round pick Jimmy Smith at the cornerback spot opposite of Cary Williams.

In six games this season, Webb had 25 total tackles, six pass deflections and one interception.

This story originally appeared on SBNation.com.