The league announced Thursday that all discipline issued to Garrett was upheld upon appeal by James Thrash, the appeals officer jointly appointed by the NFL and NFLPA.
NFL Network Insider Ian Rapoport added that Garrett was also fined $45,623, per a source informed of the situation.
Following last Thursday night's brawl between the Cleveland Browns and Pittsburgh Steelers in which the defensive end ripped the helmet off Mason Rudolph and hit the quarterback in the head with the hard hat, Garrett was suspended for, at minimum, the remainder the season and playoffs, and indefinitely pending a meeting with the commissioner's office prior to reinstatement.
Thrash heard Garrett's appeal in person on Wednesday.
In the end, the harsh punishment for the helmet swing stuck.
How long into the 2020 season Garrett might miss will be determined in the offseason.
The NFL also announced appeals officer Derrick Brooks reduced the suspension of Maurkice Pouncey from three games to two games and upheld the $35,096 fine.
Pouncey came to the defense of his quarterback, attacking Garrett after the helmet swing, punching and kicking the defensive end while he was on the ground. The league reduced the suspension by one game, but Pouncey will still miss the rematch with the Browns in Week 13.
Other fines for the fight have yet to be handed down by the league office. NFL Network's Tom Pelissero previously reported that Rudolph is expected to be find for his role.