World No. 13 Marin Cilic beat Lukasz Kubot in straight sets to reach the second round of the Shanghai Masters on Monday.
The Croatian tenth seed hit eight aces to beat his Polish opponent 7-5, 6-3 on the hard court.
In the second round, Cilic will play Martin Klizan of Slovakia, who beat Brazil’s Thomaz Bellucci 6-3, 6-4 on Sunday.
Elsewhere, Italy’s Andreas Seppi beat Michael Berrer of Germany 6-2, 7-6(5) to set up a second-round clash with fourth seed Tomas Berdych of the Czech Republic.
World No. 2 Novak Djokovic, who won the China Open for a third time on Sunday, will play Grigor Dimitrov in the second round after the Bulgarian defeated Pablo Andujar 7-5, 6-3 in the first round.
Like Djokovic, Roger Federer has a bye in the first round, and will play either China’s Zhang Ze or Taiwan’s Lu Yen-Hsun in the second round.
If Federer reaches the quarterfinal, he will retain his world No. 1 ranking, but failing to do so allows Djokovic to claim the top spot by winning the tournament.
The prize fund for the tournament is over $3.5 million.