Marin Cilic beats Gilles Muller to reach Rotterdam quarterfinals

Cilic, Monfils advance to Rotterdam quarterfinals (5:00)

Marin Cilic holds off Gilles Muller, Gael Monfils defeats Borna Coric and Gilles Simon cruises past Robin Haase in the second round in Rotterdam. (5:00)

ROTTERDAM, Netherlands -- Second-seeded Marin Cilic reached the World Tennis Tournament quarterfinals by defeating Gilles Muller of Luxembourg 7-6 (2), 7-6 (7) in the second round on Wednesday.

Neither player faced a break point in the first set, but Muller saved five in the second.

Cilic had two match points at 6-4 in the tiebreak, then saved a set point at 7-6 down as Muller fought back strongly.

"I was expecting a close match," said Cilic, runner-up here to Tomas Berdych two years ago. "Luckily, I was serving well, and I was mentally focused. Gilles is a very difficult player to play against indoors, and I'm happy to be through."

Cilic, the 2014 U.S. Open champion, next plays Philipp Kohlschreiber of Germany, who won against qualifier Ivan Dodig of Croatia 6-4, 6-2.

Kohlschreiber proved clinical on Dodig's serve, converting four of five break-point chances, and was solid on his own, winning 75 percent of points on second serve.

Meanwhile, fifth-seeded Gael Monfils of France beat 19-year-old Borna Coric of Croatia 6-3, 5-7, 6-2 in a match littered with 22 break-point chances.

Monfils served for the match at 5-4 in the second set, then lost three straight games.

He finally served out the victory to set up a match against either countryman Gilles Simon, seeded third, or German teenager Alexander Zverev. Simon and Zverev each won their first-round matches on Wednesday.

In other first-round play, No. 8-seeded Viktor Troicki, Jeremy Chardy, and Roberto Bautista Agut also advanced.