Dart, 23, suffered the injury on the first drive of Monday night’s game when his left leg bent awkwardly after contact with two Rams defenders, prompting an immediate assessment that suggested a medial collateral ligament (MCL) sprain.
An MRI performed later revealed tears to the MCL, posterior cruciate ligament (PCL) and meniscus, a diagnosis reported by NFL Network. Head coach John Harbaugh, who is in his first season with the Giants, said the evaluation process was still ongoing on Tuesday and confirmed the severity of the injury on Wednesday.
The loss is a major blow for Harbaugh, whose tenure began with a home victory over Dallas in Week 1. With Dart sidelined, veteran Jameis Winston will assume the starting quarterback role beginning Sunday’s matchup against Tennessee. Winston, who has a 3‑9 record in 12 starts since 2024, will be tasked with guiding a team whose next five opponents have a combined 2‑8 record.
Other injury updates from practice included edge rusher Brian Burns, who sprained his left ankle in the Rams game, and starting left tackle Andrew Thomas, who left with a groin strain. Wide receiver Malik Nabers, who recently popped his shoulder back into place, participated in the unpadded session.
Harbaugh is scheduled to address reporters after practice on Wednesday, where he is expected to outline the team’s plan for the remainder of the season without Dart.