Dallas Cowboys Pro Bowl left guard Tyler Smith will have surgery on his sore left thumb on Tuesday. He is expected to sidelined four-to-six weeks, per coach Brian Schottenheimer.

Smith will be placed on injured reserve.

T.J. Bass will start in his place in Sunday’s season opener against the New York Giants and for the forceable future.

Schottenheimer said Smith has been dealing with the thumb since training camp. They hoped he could play through it but realized he couldn’t function as he needed to.

“I think at the end of the day, you always think he can kind of play through these things,” Schottenheimer said when asked why they didn’t do the surgery earlier. “He’s done things like that.”

Schottenheimer said it was a ligament issue on his thumb.

The Cowboys are confident in Bass’ ability to hold the fort in Smith’s place.

But losing Smith is a huge setback.

He is not only the team’s best and highest paid offensive lineman. But he is regarded as the best interior lineman in the NFL.

The Cowboys have had a drama free training camp and preseason.

Now, they are heading into a season that was full optimism with a little adversity.