The NFLcalendar may be changing. (Gene J. Puskar / AP) Von Miller is currently appealing a four-game suspension by the NFL. (Gene J. Puskar / AP)

Updated with details, Miller statement

Von Miller, the Denver Broncos’ linebacker, is facing a four-game suspension from the NFL for violating league policy, according to multiple reports.

Miller, defensive rookie of the year in 2011, is presently appealing the discipline, according to ESPN. The Denver Post reports that Miller tested positive for amphetamines and marijuana during his rookie season. Under NFL policy, a positive test for a recreational drug lands a player in a program, and a second triggers a four-game suspension. Testing positive for a performance-enhancing drug results in immediate suspension.

Miller issued a denial on Twitter, saying:

The NFL Players Association was not pleased that the information leaked out and George Atallah, the NFLPA’s assistant executive director of external affairs, tweeted today:

If Miller fails to win on appeal, the Broncos would open the season against the Baltimore Ravens without two of their key defensive players. Elvis Dumervil was released during the offseason and signed with the Ravens, who will play the season opener Sept. 5 in Denver.

Miller would also miss games against the New York Giants, Oakland Raiders and Philadelphia Eagles.

Last week, the Broncos suspended Matt Russell, the director of player personnel, and Tom Heckert, the director of pro personnel, without pay for one month because of drunken-driving arrests.

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