IRVING, Texas >> Tony Romo’s dramatic return from his latest back injury doesn’t mean he is cleared to face the next opponent.

Coach Jason Garrett said Tuesday that Dallas was waiting on additional testing for an injury he says is unrelated to the herniated disk Romo sustained in Washington last December, when surgery kept him out of a season-ending loss to Philadelphia with a playoff berth on the line.

Romo hurt his back against the Redskins again Monday night, getting what Garrett called a contusion on a third-quarter sack. X-rays were negative, and Romo took a pain injection before returning for the final series of regulation and a failed possession in overtime of a 20-17 loss that snapped Dallas’ six-game winning streak.

After saying on his radio show earlier in the day that he anticipated Romo being ready to face the Cardinals (6-1), Garrett was more evasive when he met with reporters. The coach said Romo "seemed good" when they spoke by phone, but he hadn’t seen the quarterback before Romo went for a CT scan.

The Cowboys (6-2) were off Tuesday, and Romo has skipped the Wednesday practice every week during the regular season as part of his post-surgery routine. He had a procedure to remove a cyst from his back in April 2013 and missed all the offseason workouts last year.

"We’ve just got to wait and see how he feels, obviously," Garrett said. "Because we played late last night, we’ll be more abbreviated anyway, more of a jog through-type mode."

Garrett said it was a medical decision to allow Romo to return, but didn’t discount the resolve of a quarterback who led a comeback victory over the Redskins while playing with the herniated disk and did the same thing against the 49ers in 2011 with cracked ribs and a punctured lung.

Romo didn’t even come close to a rally this time. The last drive of regulation, starting at the Dallas 3, stalled after one first down. The game ended in the extra period on a four-and-out sequence when the Cowboys couldn’t convert second-and-2 on three straight pass plays.

"He’s been in this kind of situation before and played very well," Garrett said. "He’s very credible. He’s mentally and physically tough. He seemed capable of doing what we asked him to do on the sidelines. I think we made the right decision. Unfortunately it didn’t work for us."

The Cowboys scored on both possessions Romo missed, with backup Brandon Weeden getting a boost on his first snap from Murray’s 51-yard run to set up a field goal. Weeden then led an 80-yard drive capped by a 25-yard touchdown pass to Jason Witten.

Garrett dismissed the notion of whether he considered sticking with Weeden once owner Jerry Jones delivered the news to him on the sideline that Romo would be able to return.

"Tony is our starting quarterback, so there’s no discussion there," Garrett said. "If Tony was capable of playing and if Tony was functional and able to play, Tony was going to go back in when he was ready to do so."

And Romo didn’t think the injury had anything to do with a closing sequence that included his fifth sack and an intentional grounding penalty on third-and-1.

"I think it was their defense on the last series or two that affected it more than anything else," Romo said. "They had the right call on a couple times that took away what we wanted."

The question now is whether the Redskins took away Romo for another game, or longer.