The Cowboys will indeed face the first four games of the season without defensive lineman David Irving, who is suspended by the NFL without pay for violating its policy on performance-enhancing drugs.

An official announcement of the penalty Wednesday signaled that the third-year player's appeal was rejected. It was expected. Dallas has known since May that the 6-7, 273-pound mismatch and 2016 team leader in quarterback pressures would probably be punished. According to a source, he took a banned over-the-counter substance.

Irving will be able to participate in training camp and all preseason practices and games. But the Cowboys won't have one of their most promising pass rushers in games against the New York Giants, Denver Broncos, Arizona Cardinals and Los Angeles Rams.

Irving's development last season into a headache for opposing quarterbacks and offensive linemen gave the Cowboys every reason to look forward to more in 2017. The sticking point with Irving has been consistency, and now he can't show up in games until Oct. 8 at the earliest, against the Green Bay Packers.

This is the fourth straight year that the Cowboys will open the season with at least one defensive starter or key contributor suspended. Dallas is also without end Randy Gregory, who was suspended in early January without pay for at least one year after multiple violations of the NFL's substance-abuse policy.

Irving played 45.9 percent of the defensive snaps last season, finishing with four sacks, five tackles for loss, 26 quarterback pressures, five passes defended and four forced fumbles -- three of which came while only playing 19 snaps in the regular-season win over Green Bay.

He also stood out in the win over Tampa Bay, compiling 11/2 sacks, five quarterback hits and a pass defended in the fourth quarter alone.

David Irving suspension no surprise. Today's announcement means the Cowboys DE has had his appeal heard and denied. — David Moore (@DavidMooreDMN) June 28, 2017

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