ARLINGTON, Texas — Tony Romo knew he was risking another left collarbone injury by coming back eight weeks after breaking it.
The Dallas quarterback won't have to worry about another return. He's out for the season this time.
Cowboys owner and general manager Jerry Jones said on his radio show Friday that Romo would sit out the remaining five games with a small fracture in the same collarbone that had already sidelined him for seven games.
Romo will not need surgery after getting hurt in the third quarter of Thursday's 33-14 loss to Carolina. He didn't need surgery after breaking the collarbone in Week 2 at Philadelphia, either.
It's the third fracture in Romo's non-throwing shoulder in his nine-year career as the Dallas starter. He missed most of 2010 after getting hurt against the New York Giants.
"The hard part is playing when you're trying not to get hurt, which is silly," Romo said after he threw three interceptions and Carolina returned two of them for touchdowns before the injury. "I'm disappointed in costing our team a good chance to stay in the game early. Then on top of it, who knows how long after that. It's just a disappointing day."
Romo was in his second game back after the Cowboys (3-8) lost seven straight without him. The skid ended in his return at Miami, and the Carolina loss was his first of the season.
"We felt that the risk was worth the potential of having him be the impact he can be and he is on our team," Jones said on his radio show. "You shouldn't ever quit trying to do something that is extraordinary. The dream was if Tony could have come in, been the catalyst, played similarly and had results we had the week before against Miami ... that it would've been the beginning of maybe something special."
Matt Cassel, who started four games during Romo's first absence, will be the starter as long as he's healthy. He lost all four of his starts after Brandon Weeden was 0-3 filling in for Romo. The Cowboys released Weeden the week Romo was activated, and he signed with Houston.
"You have to step in and try to fulfill that role," Cassel said after leading Dallas' only touchdown drive against the Panthers. "Hopefully the guys rally around you. You have to move forward. I have confidence in myself and confidence in this team."
The 35-year-old Romo is becoming injury-prone late in his career. He's had two back surgeries since 2013, and a third back injury that sidelined him for a game last year. He also played through broken ribs and a punctured lung earlier in his career. He missed two games in 2008 with a broken finger.
"We wouldn't let Tony play if he wasn't ready to play physically," coach Jason Garrett said after the game. "There is no evidence we brought him back too soon."
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