Romo stayed on the ground for a couple of minutes, hesitant to move and wincing in obvious pain while trainers examined him.
After an effective Brandon Weeden led a pair of scoring drives, Romo made a dramatic return in the fourth quarter with under two minutes left and the game tied at 17. Washington held on to win 20-17 in overtime after Romo failed to move the offense on the final possession of regulation and his once chance in overtime.
Coach Jason Garrett said after the game that his signal-caller has a back contusion and X-rays were negative. Romo revealed that he had to take an injection to continue playing.
"I think the doctors do a great job ... I trust them exclusively," Romo added. "I've played the game long enough (and) sometimes you feel certain things that you just can't really go through, and then others you think you can, and I just felt like -- it was obviously painful -- but I also felt like I could deal with it, and I've done that before and just played football."
Jerry Jones told reporters, "It was a sound decision. I didn't think we were risking anything. ... It was a contusion."
UPDATE: Garrett said at a Tuesday news conference that Romo had a scan on his back, but the team continues to wait on results.