Aryna Sabalenka, Danielle Collins to square off in Rome semifinals

(Photo credit: Andy Abeyta/The Desert Sun / USA TODAY NETWORK)

Any worries about Aryna Sabalenka's ailing lower back were put to rest Wednesday when the World No. 2 defeated Jelena Ostapenko 6-2, 6-4 in an efficient 72 minutes to move into the semifinals of the Internazionali BNL d'Italia in Rome.

"I was testing my body on the warmup and I felt, 'OK, I'm probably going to go on the court and play,'" she told reporters of