Bad news for the Dallas Cowboys, as defensive end Robert Quinn is being suspended for two games, according to Ian Rapoport of NFL Network. The veteran pass rusher was slapped with the ban for violating the league's policy on performance-enhancing substances.

It certainly hasn't been Quinn's week, as just a couple of days ago he suffered a broken hand during a training camp practice. Cowboys coach Jason Garrett said soon after that he expected Quinn to be ready for Week 1, but now it won't matter.

Quinn is undergoing surgery this week and is likely to miss the rest of camp and the preseason as well. In response to the suspension, Quinn's agent, Sean Kiernan, released a lengthy statement on Twitter:

Quinn's team is arguing that very small amounts of a banned substance contaminated his seizure medication. Kiernan explains that Quinn's pharmacy filled a prescription for the banned substance for someone else right before filling one for his seizure medication, implying there may have been trace amounts left in his.

Kiernan's letter is pretty forceful, and he contends that the league even admitted they didn't believe he was intentionally doping. Regardless, he'll now have to miss games against the New York Giants and Washington Redskins.

Quinn is in his first season as a Cowboy after spending last year with Miami. He has been on the decline recently, but he did have three straight years of 10-plus sacks from 2012-14.

Quinn started his career with the Rams and spent his first seven years with them. He had 6.5 sacks while starting all 16 games for the Dolphins last year. This is a blow to the Cowboys' pass-rush rotation, and they'll now need 2017 first-round pick Taco Charlton to step up in his place.