Mariota sustained an undisclosed injury in the first quarter of Sunday's game against the Colts in London and headed to the locker room for further evaluation, Nicki Jhabvala of The Athletic reports.
Making a second straight start in place of Jayden Daniels (elbow), Mariota completed three of four pass attempts for 46 yards and ran once for a 35-yard gain before he appeared to get hurt on a third-down sack with 7:05 remaining in the quarter. Athan Kaliakmanis came on to replace Mariota under center on the Commanders' next possession.