According to a report, Dallas Cowboys Offensive Line Coach Frank Pollack, will not be returning in 2018. He has held the position since 2015. Pollack was promoted in 2015 when Bill Callahan departed for Washington. He served as an assistant under Callahan for two years prior.

The news was reported by Alex Marvez of Sporting News. He did have a slight error on Coach Pollack’s name, however:

Not sure if out there but source tells @sportingnews that Frank Pollard is out as @dallascowboys offensive line coach

— Alex Marvez (@alexmarvez) January 10, 2018

The Cowboys have had one of the league’s best offensive lines during Frank Pollack’s tenure. Tyron Smith, Travis Frederick, and Zack Martin have gone to the Pro Bowl all three seasons. Dallas has finished 9th, 2nd, and 2nd again the last three seasons in total rushing yardage.

With three first-round picks and a lot of the salary cap invested in the offensive line, the Cowboys clearly aren’t taking the position lightly.

A major blight on Pollack’s resume is the failed development of 2015 3rd-round pick Chaz Green, who has been unable to produce consistently. His abysmal performance this year starting at left tackle against the Atlanta Falcons, which led to Dak Prescott being sacked eight times, was the lowest point yet.

While there is no indication yet who will replace Frank Pollack as the offensive line coach, it is possible that the Cowboys will once again promote from within.

Marc Colombo, who played right tackle for the Cowboys from 2005-2010, has worked under Pollack since 2015.

Last week, Dallas announced quarterback Kellen Moore would move into the quarterback coach position despite no previous coaching experience. If they’re willing to trust Moore this quickly, there’s no reason to think Colombo couldn’t move up as well.

The Cowboys may look elsewhere for a replacement, but it does appear certain that Frank Pollack is on the way out. It’s just another change in a tumultuous month for the team’s coaching staff.