ASHBURN, Va. -- Washington Commanders quarterback Marcus Mariota suffered a sprained MCL of his right knee, but the timetable for his return remains uncertain, coach Dan Quinn said Monday.
Quinn also reiterated that starting quarterback Jayden Daniels will practice in full this week, with the hope of starting Sunday against the visiting New York Giants.
Mariota had started the past two games in place of Daniels, who was sidelined with a dislocated left elbow.
Daniels has played a full game just five times since the start of the 2025 season, adding to Mariota's importance.
But after leading the Commanders to a 33-31 home win over the Seattle Seahawks in Week 3, Mariota suffered the same injury on Sunday that occurred in an Aug. 14 preseason game versus the Miami Dolphins. He was able to return to practice on Sept. 1 following August's setback.
Mariota led field goal drives on his only two series Sunday against the Indianapolis Colts for a 6-0 lead; the Commanders (1-3) would go on to lose 30-13 in London. Mariota was sacked by defensive tackle Adetomiwa Adebawore on third-and-goal from the 6-yard line, causing the signal-caller's right knee to bend.
Rookie seventh-round pick Athan Kaliakmanis relieved Mariota, completing 15-of-33 passes for 183 yards and a touchdown with one interception in his first NFL action.
Quinn said the Commanders want to see how Mariota progresses before deciding whether they need to add another quarterback.
Washington will play at the San Francisco 49ers on Oct. 19 before its bye week.