Tom Brady said Friday he will not ask the U.S. Supreme Court to block his four-game “Deflategate” suspension, ending his fight in a scandal that tested the power of the NFL commissioner and tarnished the reputation of one of the sport’s greatest players.

“It has been a challenging 18 months and I have made the difficult decision to no longer proceed with the legal process,” the New England Patriots quarterback said in a Facebook post . “I’m going to work hard to be the best player I can be for the New England Patriots and I look forward to having the opportunity to return to the field this fall.”

The decision by the four-time Super Bowl champion comes two days after his case was turned aside by the 2nd U.S. Circuit Court of Appeals. Brady’s only remaining hope to take the field when the Patriots open the season against Arizona on Sept. 11 had been a stay from the nation’s highest court, which accepts about 1 percent of the appeals submitted.

More worrisome for Brady and the Patriots, though, was the chance that he would receive a stay — which would require only the blessing of a single Supreme Court justice, in this case Ruth Bader Ginsburg — only to have the whole court later refuse to hear the case. That could allow the suspension to fall at a more inconvenient time in the season, perhaps including the playoffs.

“This decision was made in the interest of certainty and planning for Tom prior to the New England Patriots season,” the NFL Players Association said in a statement Friday.

The union said it was still considering whether to seek on its own a Supreme Court ruling that would limit Commissioner Roger Goodell’s authority to punish players. Dropping the case now would leave in place what the union called this week a “broken system that must be fixed.”

But even if the union fights on, Brady would still sit out the first four games of the season, when the Patriots face the Cardinals, Dolphins, Texans and Bills. Backup Jimmy Garoppolo, who has spent the last two years as the backup, is expected to start for New England instead.

Patriots owner Robert Kraft, who has split with longtime league allies over the punishment, renewed his complaint that the suspension was “unprecedented, unjust and unreasonable.”

“Unfortunately, this stopped being about air pressure a long time ago,” he said in a statement . “This entire process has indelibly taken a toll on our organization, our fans and most importantly, Tom Brady. His reluctant decision to stop pursuing further action and to put this situation behind him is what he feels is best for the team in preparation for this season and is fully supported by me and our entire organization.”

Brady is eligible to return in Week 5, when New England visits the Cleveland Browns. Despite the suspension, the Patriots remain overwhelming favorites to win the AFC East for the 13th time in 14 seasons, and the gambling website Bovada listed them as the top choice to win the Super Bowl.

An NFL spokesman said the league would have no comment.