LANDOVER, Md. -- Washington Commanders running back Brian Robinson Jr. was ruled out for the second half of Sunday's 45-15 loss to the Miami Dolphins with an injured hamstring.

Robinson was one of the few effective players for Washington early in the game vs. the Dolphins, carrying the ball seven times for 53 yards as the Commanders trailed 31-7 at halftime.

But Robinson did not return after Washington scored a touchdown to cut the deficit to 17-7 with 11 minutes, 20 seconds left in the half on a 1-yard sneak by quarterback Sam Howell.

Robinson leads Washington with 660 yards rushing this season; he tied his career-long with a 29-yard run in the second quarter.

Antonio Gibson replaced Robinson as the primary back, with Chris Rodriguez serving as his backup.