LONDON - Top seed Carlos Alcaraz got his grasscourt campaign up and running with a 6-4 7-6(4) victory over Australian Adam Walton to move into the last 16 at the Queen's Club Championships on Tuesday.

Playing in his first match since his epic 5-1/2 hour French Open final victory over world number one Jannik Sinner nine days ago, Alcaraz was tested by Walton who had set points in the second set before the Spaniard recovered and won the tiebreak.

Alcaraz was meant to play compatriot Alejandro Davidovich Fokina but the Spaniard withdrew due to illness, giving lucky loser Walton the chance to play the French Open champion as he warmed up for his Wimbledon title defense.

"I realized that I was going to play against Adam after my warm-up... He has played a few matches already before this one. I think he played really great tennis," said Alcaraz, the champion at Queen's Club in 2023.

"It surprised me a little bit. So I knew that I was going to struggle a little bit today, but just really happy to get the win.

"I feel super happy to be back on grass. It is a special surface, a special place to me."

Walton is ranked number 86 in the world and the Australian did not seem overawed by the occasion as he showcased some attacking tennis to hold serve until Alcaraz finally got to grips with the surface and broke to take a 4-3 lead.

Alcaraz used serve and volley to good effect, showing finesse with some exquisite drop shots while he was also virtually unstoppable on serve, sealing the opening set with an ace.

But Walton held serve well in the second set and nearly broke Alcaraz with his first break points - which were also set points - when he was 5-4 up but the Spaniard held on.

Once he forced a tiebreak, there was no looking back as Alcaraz wrapped up the contest.

Draper advances, Fritz out

French qualifier Corentin Moutet pulled off the biggest win of his career, saving a match point to stun American third seed Taylor Fritz 6-7(5) 7-6(7) 7-5 in a marathon battle.

The 26-year-old, who earned just his second career victory over a Top-10 opponent, will face Britain's Jacob Fearnley in the last 16.

Second seed Jack Draper warmed up the home crowd when he claimed an impressive 6-3 6-1 victory over American Jenson Brooksby for his first win on grass this season.

Draper had beaten defending champion Alcaraz in the second round last year and the Briton is hoping to improve on his quarter-final run.

"It's tricky coming onto the grass after clay, to adapt, I'm hitting the ball a bit late, not on time," Draper said.

"The more matches and time I have on practice courts, I'll get better and better. It's definitely a surface I really enjoy playing on."

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Australia's fifth seed Alex de Minaur bowed out of the tournament after a 6-4 6-2 loss to Jiri Lehecka while Alexei Popyrin beat Aleksandar Vukic 6-2 6-7(9) 7-6(3) in an all-Australian battle.

American sixth seed Ben Shelton, who had reached the semi-finals in Stuttgart last week, was also knocked out in a 7-6(5) 7-6(4) loss to French qualifier Arthur Rinderknech.