there was so little time left on the clock. And there was little time left on the clock because their offense had held the ball for 7+ minutes on a crucial 4th quartyer drive.
One thing I loved about the Rams this year was their ability to play small ball to an extent and have these long, defense-tiring scoring drives, where they picked up multiple first downs. What I didn't love was that once we got to the red zone, we too often had to settle for a field goal.
But back to the point, I think the offense running that long drive put the defense in a position to defend against a one dimensional Patriots team that had to throw and couldn't use the middle of the field.