The Miami Open is losing star tennis players quickly, as three of the world's top five men's tennis players have already been eliminated or withdrawn from competition. Tennis fans were excited to see third ranked Roger Federer make a return to the court in Miami after knee surgery, but a stomach virus forced the Swiss star to withdraw from the first match that he had hoped to play in since the Australian Open semifinals in January.

The ATP Tournament lost another star Saturday, as fifth ranked Rafael Nadal retired from his match against Damir Dzumhur after falling behind in the match 2-3, 6-4, 3-0. The 14-time major winner started feeling dizzy in the second set due to the humidity and heat, and he withdrew from his first match in six years.

"Everything was fine until the end of the first set," Nadal said. "Then I started to feel dizzy, not very good. It was getting worse and worse. Finally, in the second set, I realized that I could not keep playing. I wanted to finish the match, but I seriously could not. It was tough because I felt I was playing well."

Fourth ranked Stan Wawrinka also saw his chances of winning the Miami Open come to end on Saturday, as he fell to 25-year-old Andrey Kuznetsov in straight sets 6-4, 6-3. The 51st ranked Kuznetsov avenged his straight set loss to Wawrinka at Indian Wells last week and now faces 64th ranked Adrian Mannarino in the round of the 32.

While the Miami Open has seen star players dropping out of the tournament early, both the world's top ranked player Novak Djokovic and second ranked player Andy Murray have moved onto the round of 32. Djokovic faces 38th ranked Joao Sousa from Portugal in the round of 32 and is 2-0 all time against the 26-year old.

Murray will face 28th ranked Grigor Dimitrov in the next round, and he holds a 6-2 record over the Bulgarian and has won their last three meetings. The Miami Open has lost some of tennis' major stars early in this year tournament but could still hope for a star-filled Final, as Djokovic and Murray could be on pace to meet each other in the Final.

There are still plenty of the world's greatest men's tennis players left in this year's tournament, as Kei Nishikori, Tomas Berdych, David Ferrer, Jo-Wilfried Tsonga and Richard Gasquet have all moved on to the round of 32, which should only make the rest of the Miami Open that much more exciting.