GREEN BAY, Wis. — Vikings quarterback Kirk Cousins left Sunday’s 24-10 win over the Packers midway through the fourth quarter because of what the team termed a right ankle injury.

After the win, a source told ESPN’s Adam Schefter that Cousins tore his Achilles. An MRI will be taken to confirm the diagnosis.

Cousins, who has missed only one NFL start for health reasons in his career, was replaced by rookie quarterback Jaren Hall. Veteran backup Nick Mullens is on injured reserve because of a back injury.

The play occurred with 9 minutes, 50 seconds remaining with the Vikings holding a 24-10 lead. As Cousins stepped up in the pocket on a third-down dropback, his right leg buckled and he was sacked. Cousins managed to stand up on his own but hopped off the field while holding his right leg in the air.

To that point, Cousins had completed 23 of 31 passes for 274 yards and two touchdowns.

Cousins, 35, is due to become a free agent after the season. He and the Vikings agreed to table negotiations on a contract extension last spring, making this season a referendum on his Vikings tenure. He entered Week 8 ranked second in the NFL in passing yards and first in touchdown passes.