Collins, who announced in January that she would retire from professional tennis at the end of this season, won 89.7 per cent of her first serve points against 23rd seed Garcia.

She never faced a break point and converted three of her eight break-point chances.

The victory, sealed in a tidy 80 minutes, marked the first time Collins has won five consecutive matches on the WTA Tour since the Australian Open in 2022, when she reached her first grand slam final.

Since losing her first set in Miami to compatriot Bernarda Pera, Collins has won 10 in a row and lost only 19 games.

Her 80-minute win against Garcia, who beat Naomi Osaka and Coco Gauff in back-to-back rounds to reach the quarter-finals in Miami for the first time, marks her third win against a seeded player in five matches over the past seven days.

She has also got the better of Romania's Sorana Cirstea (19th seed) and Anastasia Potapova (30th) of Russia.

"Caro comes out here and fights her butt off," Collins said in her on-court interview.

"She hits some really strong shots ... I don't think the set scores are a reflection of how close the match really was.

"Against someone like Caro, it forces me to be more concentrated, because I know I don't want to give her an inch."

Up next for the 30-year-old Collins will be either fifth-seeded compatriot Jessica Pegula or Russian 14th seed Ekaterina Alexandrova.

Australian Associated Press