Mark Sanchez of the Jets looks on in the fourth...

Mark Sanchez of the Jets looks on in the fourth quarter against the Bills at MetLife Stadium on Nov. 27, 2011. Credit: Jim McIsaac

Former Jets quarterback Mark Sanchez has been suspended for the first four games of the 2018 season for violating the NFL’s performance-enhancing drug policy, the league announced Friday afternoon.

Sanchez, 31, is a free agent. He was the Bears’ third-string quarterback last season but did not play.

Sanchez put a statement on Instagram acknowledging the suspension and placing the blame on “unknowing supplement contamination.”

“The NFL has informed me that I have tested positive for a substance on the banned substance list,” he wrote. “I was blindsided by the news and I want to say unequivocally that I have never cheated or attempted to gain a competitive advantage by using a banned performance-enhancing substance.

“During the past nine years as an NFL player, I have been subject to 73 drug tests — and all but one have been clean. I have taken the same regimen of supplements for the past five years without issues. The timing and results of my tests establish circumstances of unknowing supplement contamination, not the use of performance-enhancing substances.”

Sanchez was drafted fifth overall by the Jets in 2009. He played his first four seasons for the Jets, including runs to the AFC Championship Game in the first two.

Sanchez missed the 2013 season after undergoing surgery on his throwing shoulder and was released in 2014. He had a roller-coaster career with the Jets that some will remember for his infamous “Butt Fumble’’ against the Patriots on Thanksgiving night in 2012.

He played the 2014 and 2015 seasons with the Eagles, making 10 starts, and appeared in two games for the Cowboys in 2016.

Newsday staff

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