Seeds Petra Martic and Coco Gauff were victorious at the Emilia-Romagna Open on Wednesday, but injury cut short Sara Sorribes Tormo's run in the tournament.
Gauff recorded five breaks of serve as she overcame Italian Camila Giorgi in routine fashion, a 6-2 6-3 triumph securing the third seed a place in the quarter-finals.
The American did have a few issues on her own serve, leading to seven double faults, but ended up winning in one hour and 11 minutes.
Martic, the second seed at the event, was made to work in the first set of her match against Ludmilla Samsonova, both players saving a break point on serve as it went the distance.
There was little to split the pair in the tie-breaker too, Martic edging it 7-5 as she capitalised on her first opportunity to take the set.
The second was more straightforward for the Croatian, an early beak of serve putting her in front before she repeated the trick to wrap up victory in the ninth game.
There were wins in straight sets for fellow seeds Caroline Garcia and Wang Qiang too, as they defeated Anna-Lena Friedsam and Martina Di Giuseppe respectively.
For Garcia, the triumph means a first quarter-final appearance in the 2021 season.
Rubbing her hands with glee (and sanitizer)— wta (@WTA) May 19, 2021
A first quarterfinal of the season for @CaroGarcia!
The No.8 seed defeats Friedsam 6-2, 6-4 and will face Siniakova for a spot in the Parma last four. pic.twitter.com/Zi0MmFim6w
Sorribes Tormo was the only seeded player to exit in the day’s action, the Spaniard forced to retire at 2-2 in the deciding set against Sara Errani due to a problem with her left thigh.
"I'm very sorry for Sara. It was a battle, I know every time we play together it is like this. I was mentally ready to fight, to suffer," Errani said in her on-court interview.
Top seed Serena Williams is already out, beaten in straight sets by Katerina Siniakova to deal the 23-time grand slam champion a further blow ahead of this year's French Open.