Frances Tiafoe has advanced to an all-American semi-final at the US Open after Grigor Dimitrov was forced to retire for a second straight grand slam.
Tiafoe, the 20th seed, led 6-3 6-7 (5-7) 6-3 4-1 on Tuesday (Wednesday AEST) when ninth seed Dimitrov pulled the pin with a leg injury.
The Bulgarian has enjoyed a resurgence in recent times but form has not been matched by good luck on the biggest stage, having already been forced to cut short his fourth-round match at Wimbledon in July.
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He played a five-setter in the fourth round and appeared to be fading late in the third set against Tiafoe.
Having grabbed at his left hamstring while walking gingerly between points, he was visited by a trainer during the break and headed to the locker room for treatment.
At one changeover in the fourth set Dimitrov was told by his team to pull the pin but he was determined to continue.
In the end the injury took its toll on his ability to even compete and the pain was too much to stick it out.
“So sad for Grigor Dimitrov, bad s*** shouldn’t happen to good guys,” Australian tennis great Rennae Stubbs said.
Tiafoe will now face countryman Taylor Fritz in the semi-final, ensuring an American man will make the championship match for the first time since Andy Roddick lost in 2006.
Roddick is also the last American to win the US Open, winning in 2003 the year after Pete Sampras won his fifth and last title at Flushing Meadows.
Tiafoe made the semi-finals in 2022 but fell to eventual champion Carlos Alcaraz.
Fritz, meanwhile, ended his hoodoo after previously making four grand slam quarter-finals for zero wins.
Just as he did at Wimbledon in July, the American eliminated Alexander Zverev with a 7-6 (7-2) 3-6 6-4 7-6 (7-3) victory on home soil.
The 12th seed has eyes on becoming the first men’s home champion in New York since Roddick.
“I feel amazing, I have had a lot of looks at quarter-finals over the last few years and today just felt different,” Fritz 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 know the crowd would really want to see me and Frances so we get an American in the final.
“I guess we’ll see what happens, but either way I’ll be ready to go.”
For the fourth seed Zverev, this will be a bitter pill to swallow as his quest for a first grand slam title goes on.
Wednesday’s other men’s quarter-finals see world No.1 Jannik Sinner taking on No.5 seed Daniil Medvedev and Australia’s world No.10 Alex de Minaur up against No.25 Jack Draper.
– with AAP