United States` Danielle Collins advanced to the second round of the Italian Open after former world number one Caroline Wozniacki retired because of a leg injury. For the second consecutive event, Wozniacki has withdrawn early as last week, she had an opening-round injury retirement to Alize Cornet at the Mutua Madrid Open. In the match, Collins claimed the first set of their opening-round encounter, 7-6(5) but eventually, the match stopped. World number 20, Collins will now clash with the two-time Grand Slam winner Garbine Muguruza of Spain for a place in third-round. Now, Wozniacki would hope to be fit again for the upcoming Grand Slam, French Open, which starts on May 26. "Obviously, I feel for Caroline, what she`s going through with her injuries," said Collins. Danielle Collins claimed a spot in the #ibi19 2️⃣nd round. Wozniacki retired due to injury following the first set. --> https://t.co/2S3zilmCcS pic.twitter.com/JdrZhWNRXr — WTA (@WTA) May 14, 2019 × Unfortunately, Caroline #Wozniacki had to retire from #ibi19. Get well soon.❤️ pic.twitter.com/ohnaJwmxrK — Internazionali Bnl (@InteBNLdItalia) May 14, 2019 × "It`s never fun to go out there and play against somebody that`s hurt, and dealing with that kind of pain. I was happy with the way I played, but it`s just not a fun situation."