All-Pro Denver Broncos linebacker Von Miller is facing a four-game suspension to start the 2013 season after reportedly violating the NFL's substance abuse policy. He is appealing.

Details of the suspension are scarce at this point, as Miller's punishment is currently in the appeals process. League policy is to only comment on suspension if an appeal is not made, or once an appeal fails.

To face a 4-game suspension for violating the NFL's substance abuse policy, a player must fail two tests.

Since entering the league in 2011 as the No. 2 overall pick, Miller has tallied 30 sacks and forced 8 fumbles. Both stats are 4th best in the league during that time span. He is widely considered the best defensive play on the Broncos roster, and one of the best defensive players in the entire league.

UPDATE: Miller has responded to the news via his twitter page.

@MillerLite40/twitter