Denver Broncos linebacker Dre Greenlaw's one-game suspension for unsportsmanlike conduct toward a referee has been upheld on appeal, the league announced Tuesday.
Greenlaw will miss Denver's home game against the Dallas Cowboys on Sunday.
In announcing Greenlaw's suspension on Monday, the NFL said he "chased after referee Brad Allen and verbally threatened him as he tried to leave the field" following the Broncos' win against the New York Giants at Mile High Stadium.
Video posted by a CBS Colorado reporter showed Greenlaw's encounter with Allen.
The suspension will cost Greenlaw, who must also sit out the Broncos' practices this week, a game check in the amount of $192,778.
Sunday marked Greenlaw's first game with Denver after he signed a three-year, $31.5 million contract in March. He did not play in the preseason or in the first six games of the regular season because of thigh injuries.
Against the Giants, Greenlaw played 21 snaps and finished with six tackles and a quarterback hit as the Broncos stormed back from a 19-0 fourth-quarter deficit to win 33-32 and improve to 5-2.
ESPN's Jeff Legwold contributed to this report.
