Dallas Cowboys linebacker Rolando McClain has reportedly been banned by the NFL for the opening ten games of the regular season due to a violation of the substance abuse policy.

The suspension is yet another blow to the Cowboys defense with defensive ends Randy Gregory and DeMarcus Lawrence already banned for the first four games for the same reason.

Schefter breaks news of suspension

ESPN NFL insider Adam Schefter broke the news concerning McClain’s ban on Twitter before also confirming Lawrence’s ban as a result of his appeal being denied.

This is McClain's second suspension

McClain will face his second ban in as many years after he also faced a four-game suspension at the beginning of last season.

His latest setback poses as yet another questionable episode in an extremely stop-start career.

The eighth pick of the 2010 draft by the Oakland Raiders has failed to make any real stamp on the league. He was released in 2012 as well as retiring twice in his career, undergoing knee surgery and missing organized team activities in 2015 due to family reasons.

He recorded 80 tackles, two sacks, and an interception in the 11 games he played last season. This followed a 2014 season in which he made 81 tackles and one sack in 13 games.

The 26-year-old's return to the Cowboys minicamp in June marked further disruption to his progress when his fitness emerged as an obvious concern.

Lawrence's absence means head coach Jason Garrett will also be without a man who made eight sacks in 2015. 

Garrett will now be without three projected defensive starters when the Cowboys kick off their 2016 season against the New York Giants.