Top seed Kei Nishikori crashed out in the second round of the Dubai Tennis Championships on Wednesday with a 7-5, 5-7, 6-2 loss to 77th-ranked Hubert Hurkacz of Poland.

In their first career meeting, the 22-year-old Hurkacz served nine aces and double faulted just once to upset the favorite from Japan in 2 hours and 3 minutes.

World No. 6 Nishikori, on the other hand, struggled with his serve, hitting four double faults and a solitary ace at Dubai Duty Free Tennis Stadium.

"I didn't make my first serve when it mattered, but more than that, I just couldn't find a rhythm," the 29-year-old Nishikori said.

"My opponent played well, whereas I was unable to play flawless tennis."

Both players held serve in the first set until the ninth game, when Nishikori secured the break to go up 5-4. But Hurkacz won the next three games to take the set.

Nishikori looked in control of the second set at 5-1, but his opponent rattled off four straight games to level at 5-5. The U.S. Open semifinalist broke Hurkacz in the 11th game before holding serve to even the match at a set apiece.

At 1-1 in the deciding set, Hurkacz won three games in a row to take control of the contest.

Nishikori, coming off a semifinal loss to Stan Wawrinka at the Rotterdam Open, beat France's Benoit Paire 6-4, 6-3 in the opening round on Tuesday.