The Commanders' quarterback injury woes got even worse Sunday in London: Marcus Mariota, already starting in place of Jayden Daniels (elbow), suffered a right knee injury in the first quarter against the Colts and is officially questionable to return. After a short time in the injury tent, Mariota walked back to the locker room for further evaluation.

Washington turned to third-string quarterback Athan Kaliakmanis, a seventh-round rookie out of Rutgers, getting his first career NFL snaps.

Mariota -- who relieved Daniels in the second half of Week 2 against the Cowboys and started in last week's 33-31 upset win of the Seahawks -- was off to a strong start against the Colts. Washington scored field goals on each of its first two possessions, with Mariota completing three of four passes for 46 yards and also ripping off a 35-yard run. But he went down on a red-zone sack, with his right leg getting pinned awkwardly. He was able to walk off under his own power, albeit gingerly.

Kaliakmanis was the 223rd overall pick in April's draft and won the Commanders' third-string quarterback job with a strong preseason.

The Commanders do not have a fourth quarterback on the roster behind Daniels, Mariota and Kaliakmanis; Sam Hartman is on the practice squad. Colson Yankoff, a tight end who started his collegiate career as a quarterback, would be the emergency option.

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