US Open: Frances Tiafoe victory sets up all-American semifinal

Hours after Fritz disposed of fourth seed Alexander Zverev in the quarter-final, Tiafoe followed suit by beating an injured Grigor Dimitrov 6-3 6-7 (5) 6-3 4-1.

It was not the way Tiafoe would have wanted to win as 34-year-old Dimitrov sustained an injury at the end of the third set.

He was barely able to move in the fourth set before he had to retire.

Dimitrov revealed he was disappointed with the outcome, but his overall fitness is his priority.

He said: "I think it's a combination from everything. Clearly my rehab process is a little bit slower than before. I felt a couple of things in prior the match.

"I think I have enough experience in myself to know where there's no point to continue any further on that, and I think it's just simple as that. Do I like doing it? No, but that's that."

Fritz and Tiafoe will face off on Friday night, guaranteeing a home player in the men's final since Andy Roddick lost to Roger Federer 18 years ago.

It will also be the first all-American semi-final in a men's grand slam since 2005.

Now there is a real chance of a home winner in New York for the first time since 21 years ago, with Tiafoe telling the press that beating Dimitrov due to an injury was "not the way he wanted to get through".

"But, I'm happy to get through. Another semi-final here. Incredible," he said.

"It was a really high-level match, I liked where I was at in the third regardless, but I didn't want to end it like that."

He added: "But you get to see me against another American so Friday is going to be one hell of a day."

He called Friday's match the "biggest" of both his and Fritz's life.

"We have known each other for so long, we have played against each other since we were 14," he said.

"To play him here in the biggest arena, in one of the biggest matches in the world, is going to be awesome.

"I can't be more excited, I am going to give it everything I have got."

Fritz earlier ended his quarter-final hoodoo by reaching the last four.

The 26-year-old American had lost all of his previous four last-eight matches at a grand slam but put that right on home soil by beating Zverev 7-6 (2) 3-6 6-4 7-6 (3) on Arthur Ashe.

"I feel amazing, I have had a lot of looks at quarter-finals over the last few years and today just felt different," he said.

"I really felt like it was my time to go a step further. It's only fitting I'm doing it here on this court at the Open in front of this crowd.

"I think the way I came out today was different because I just have been in this situation enough times.

"I think a question I got asked pretty much every time I lost in my quarter-finals was, 'What's it going to take to go further?', and the answer I gave was always, just keep putting myself in these situations, and I'll become more comfortable in these situations and get better."

He added: "That's definitely what happened now. The quarter-finals didn't feel like, I don't know, this big thing to me like it has been, I guess, in the past. It just felt like another tournament."

For Zverev, it may be a bitter pill to swallow as his quest for a first grand slam title goes on.

The German, a US Open finalist in New York in 2020, did not think much of his performance.

"I played terrible. Terrible. Just absolutely terrible by me," he said. "I have no words for it, to be honest."