Goran Ivanisevic believes that 18-year-old Borna Coric could win multiple Grand Slams. The former Wimbledon champion coaches Marin Cilic, and he's watching Coric closely.

At the start of this year, Coric was ranked No. 92 but he has risen to No. 38. The only teenagers in the Top 100 are No. 58-ranked Hyeon Chung, No. 71-ranked Thanasi Kokkinakis and No. 78-ranked Alexander Zverev.

"Definitely Coric] can win a Grand Slam," Ivanisevic [told *CNN*. "He's one of the five, six guys that is definitely going to dominate in men's tennis in the next five or 10 years."  
This year, Coric qualified in Doha and reaching the semifinals, upsetting Andy Murray before losing to Roger Federer. At the French Open, he beat Sam Querrey and Tommy Robredo before falling to Jack Sock.

Coric lost in the first round at the U.S. Open, so he went to play in a Challenger in Brazil on clay and won the title. A week later, he won both his Davis Cup matches against Brazil during Croatia's win.

"I saw him for the first time when he was 12 years old," Ivanisevic said. "When somebody has something, that thing that you cannot buy, that you cannot learn, you have to be born with it. The way he plays points, the way he's fighting, he's like a pit bull. When a pit bull bites, he doesn't let you go. That's him."