By Martyn Herman
LONDON, July 7 (Reuters) - American Coco Gauff and Germany's Alexander Zverev both broke new ground at Wimbledon on Tuesday but Naomi Osaka's title hopes evaporated on a boiling hot day at the All England Club.
Hot weather warnings might have furrowed the brow of men's defending champion Jannik Sinner but he tamed German veteran Jan-Lennard Struff 7-5 7-6(4) 6-3 to reach the semi-finals.
Seventh seed Gauff's relationship with grass has been lukewarm since she made her Wimbledon debut
as a 15-year-old in 2019 and had never gone past the fourth round.
The bond is clearly getting stronger though as she proved with a composed 4-6 6-3 6-3 victory over American number one Jessica Pegula on Centre Court.
OSAKA'S BID FOR FIFTH MAJOR HALTED
Zverev, whose Wimbledon ceiling had also previously been the fourth round, returned to finish off dangerous Czech Jiri Lehecka to reach his first quarter-final there.
The 29-year-old had been three games from victory on Monday evening before being snagged by Wimbledon's curfew and despite allowing Lehecka back into the match on the resumption he completed a 6-4 7-5 3-6 7-6(6) win.
He will be back on court on Wednesday to face American Taylor Fritz in a battle of the 140 mph servers.
Japan's Osaka's outfits and tennis have sparkled in equal measure at this year's Championships, and her dominant victory over world number one Aryna Sabalenka on Sunday had many predicting she could go on and win a fifth Grand Slam title.
The 14th seed ran into inspired Czech Karolina Muchova in the quarter-finals on Tuesday, however, losing 7-6(4) 6-4.
On a day of personal bests, Muchova also ensured her deepest Wimbledon run after twice falling in the last eight and she will now stand in the way of Gauff.
GAUFF'S GRASS DROUGHT ENDING
Muchova could be joined in the semi-finals by a second Czech on Wednesday when Linda Noskova plays Elise Mertens.
Gauff's progress at this year's Wimbledon has been far from smooth, dropping sets in three of her four matches.
But she is finding ways to win. Friend and doubles partner Pegula, playing her first ever match on Centre Court, looked the more assured player for a set and a half on Tuesday but Gauff solved the puzzle for an impressive victory.
"Pretty insane, honestly," was Gauff's immediate reaction to the win. "Considering how I hadn't won a match on grass in two years before this tournament, I'm definitely just really happy with how I played today."
Zverev lost 12 of the first 13 points as he resumed at 3-3 in the third set against Lehecka and looked heavy-legged as all his good work on Monday appeared to be unravelling.
But he steadied the ship and despite serving a double-fault on match point in the fourth-set tiebreak, he got it done.
"Who would have thought it's only taken me 12 years to get (to my first Wimbledon quarter-final), but I'm incredibly happy and relieved. But of course I want to play three more matches," he said on a paint-peeling day in London SW19.
NO SWEAT FOR SINNER
Sinner's second-round meltdown in a Parisian heatwave a few weeks ago has raised doubts about the red-haired Italian's ability to operate in extreme temperatures.
He never managed to find top gear against Grand Slam quarter-final debutant Struff and things might have got sweaty if he had not saved a set point in the second set.
But, ultimately his precision serving eased him through to his 10th Grand Slam semi-final and a possible collision with seven-time champion Novak Djokovic.
Djokovic was in action against Canada's Felix Auger-Aliassime in the day's final singles action.
(Reporting by Martyn Herman; Editing by Alison Williams)
