No. 1 seed Jannik Sinner and No. 5 Daniil Medvedev are headed for a blockbuster quarterfinal matchup on Wednesday at the U.S. Open.

But this showdown feels more like a final, and indeed, looks like the “real” final of this fortnight.

Sinner and Medvedev are the only two Grand Slam champions remaining in the men’s draw and — with No. 2 Novak Djokovic and No. 3 Carlos Alcarz having been eliminated early — the winner will be the favorite to hoist the trophy on Sunday evening.

“Hopefully we can have a great match,” Medvedev said after destroying Nuno Borges of Portgual, 6-0, 6-1, 6-3. “I know if I want to beat him, I need to be at my best, which I managed to do couple of times. It’s going to be a great match.”

Medvedev, 28, is 7-5 against Sinner, and was victorious in their most recent match, a five-set thriller in the Wimbledon quarterfinals.

But Sinner, 23, has won five of the previous six encounters, including a five-set win in the Australian Open final where he came back from two sets down for his first Slam title.

In that match, Sinner, a former junior skiing star, became the first Italian man or woman to win the Australian Open crown and just the eighth man to overcome an 0-2 deficit in a major final.

“I will try to think more about Wimbledon than Australian Open,” Medvedev, who won his only major over Djokovic in straight sets in the 2021 U.S. Open final, said with a smile.

“I feel like in a way we know our game, what we will try to bring on the table, and then it comes to always, you know, this moment’s deuce, breakpoint, maybe try to surprise him or not, what he will do, what I will do.”

While Medvedev cruised in his fourth-round match on Labor Day, Sinner was tested by No. 14 American Tommy Paul, 7-6(3), 7-6(5), 6-1, during breezy conditions on Monday night.

“It’s different than day sessions, but it was nice to be part of this match,” Sinner said. “You know, playing against an American here on this court in any case is difficult. Night sessions, that gives a bit more tough atmosphere. And matches, in my mind, it’s nice to be part of it. We both try to make a good match out of it, which they come to see a good match.”

Sinner has seemingly moved past the pre-tournament controversy in which the world No. 1 tested positive for a banned substance but avoided punishment.

The International Tennis Integrity Agency (ITIA) cleared Sinner after he failed two drug tests in March, but he has always maintained his innocence, saying the amount of clostebol found in his system was less than a billionth of a gram.

Djokovic called for “clear protocols” and “standardized” approaches to doping cases while Australian Nick Kyrgios said Sinner should have been banned no matter the manner of doping, whether it was “accidental or planned.”

Still, Rafael Nadal defended Sinner.

“I have a virtue or a deficit, which is that in the end I usually believe in people’s good faith. I know Sinner, I don’t believe that Sinner has ever wanted to dope,” the 22-time major champion told Spanish television show “El Hormiguero.”

“I don’t think we have to like it only when it is resolved in the way we think. In the end, justice is justice and I believe in justice.

“I believe in the bodies that have to make decisions and that really make them based on what they believe is right.”

Still, those close to Sinner say he has learned who his friends are — and who they aren’t — and that he has tightened his circle in the wake of this incident.

After dropping the first set in his first match against American Mackie McDonald and raising speculation that the off-court issue was a distraction, Sinner hasn’t dropped a set since.

“He’s unreal out of the corners,” said Paul, who was bidding to join fellow Americans Taylor Fritz and Frances Tiafoe in the quarterfinals. “Hits a quality ball every time the ball is on his racquet. I mean, that’s kind of what separates him.”

The Sinner/Medvedev winner will get the winner between No. 10 Alex De Minaur of Australia and No. 25 Jack Draper of Great Britain in the semis. Both of those players have an excellent chance to break through to their first major semifinal.

De Minaur is into his third straight Grand Slam quarterfinal of 2024, while Draper is into his maiden major quarterfinal. ESPN’s Brad Gilbert said Draper is playing at such a high level, the 22-year-old left-hander is a “legitimate threat” to win the title.

The two Americans — Fritz and Tiafoe — are on the bottom half of the draw that has been vacated by Djokovic and will play their quarterfinals Tuesday. Fritz gets No. 4 Alexander Zverev in the afternoon session, while Tiafoe faces No. 9 Grigor Dimitrov at night.

The winners of those matches will have a full two days rest before Friday’s semifinals.

Both Americans have a legitimate shot to reach the semis, and an all-American semifinal would certainly go a long way toward bolstering the argument that American men’s tennis is on the uptick.

No American man has won a Grand Slam title since Andy Roddick at the 2003 U.S. Open. Roddick turned 42 on Friday.

“Give them a break, they know it’s been a while but they’re getting closer to coming through big time,” John McEnroe said on ESPN of the Americans.

Still, the Sinner/Medvedev winner will emerge as the tournament favorite, with Sinner looking to equal Alcaraz by winning his second major of the year and Medvedev seeking the second major of his career.

The hope for the rest of the field has to be that the two Europeans will grind each other down in a five-set epic, leaving the door open for someone else to break through.

“Obviously we have two Americans still left in the tournament, but, you know, it’s never really felt this open, in a way,” Paul said.

“So I believe that one of us can do it at some point.”