Alex De Minaur got back to winning ways, overcoming a stern test from Gabriel Diallo in his opener at Queen's.

Diallo pushed De Minaur all the way in the first set, but the Australian eventually prevailed 7-6 (10-8) 6-3 in just over two hours.

The pair traded breaks twice in the first set, with neither able to gain a proper advantage as they went all the way to the tie-break.

De Minaur then raced into a 5-3 lead, but Diallo clawed his way back into the match to take the lead before failing to convert two set points.

The top seed then had to dig in deep in order to get a vital break to take a 3-1 lead in the second, eventually converting his fifth break point in the marathon 15-minute game.

From there, he remained in control, though Diallo held off two match points to claw back to 5-3, but De Minaur got over the line in the next game.

Earlier in the day, Adrian Mannarino claimed his 77th tour-level victory on grass as he defeated Jakub Mensik in three sets.

The Frenchman claimed a 5-7 7-6 (7-3) 7-6 (7-5) victory over the 20-year-old to book a meeting with Arthur Fery in the last 16.

De Minaur gets back on track

De Minaur looked strong in his first grass-court tournament of the year, but fell at the final hurdle as he was beaten to the Rosmalen Grass Court Championship title by Kamil Majchrzak.

And he had to grind to get over the line against Diallo, especially as he only managed to convert three of the 10 break points he forced.

De Minaur was also helped by Diallo's unforced errors as the Canadian made 35 to the Australian's 14.

As for Mannarino, he showed his grass-court prowess as he edged past Mensik in a lengthy contest. His 77 wins are the third-most on the surface among active players, behind only Novak Djokovic and Marin Cilic.