The decision, made by appeals officer James Thrash, means Garrett will remain suspended without pay for at least the remainder of the 2019-20 campaign. The defensive lineman will be required to meet with the commissioner's office before being reinstated.
With seconds left in the fourth quarter of last Thursday's game between the Browns and Steelers, Garrett ripped off Pittsburgh quarterback Mason Rudolph's helmet and struck him in the head with it, which sparked a melee between players from both teams.
In the aftermath of the altercation, the NFL handed down the longest ban for a single on-field incident in league history Friday, indefinitely suspending Garrett without pay for his role in the brawl. Rudolph, who appeared to kick Garrett in the groin and attempted to pull the pass-rusher's helmet off after being taken to the ground, was fined an undisclosed amount for his role in the fight.
Pouncey initially was issued a three-game ban for punching and kicking Garrett during the fight. Browns defensive lineman Larry Ogunjobi was handed a one-game ban for a late shove on Rudolph. On Wednesday, the league upheld Ogunjobi's suspension.
Both teams were also fined $250,000 each, and the NFL could still hand down "additional discipline" to other players under the league's standard accountability process, including individuals who left the bench area and ran onto the field.
The Steelers and Browns will meet again Dec. 1 at Heinz Field in Pittsburgh.