Acapulco, Mexico (SportsNetwork.com) - Top-seeded Kei Nishikori moved on during Tuesday's first round at the $1.4 million Mexican Open tennis event with a straight set victory over Alejandro Gonzalez.

Nishikori had to battle through the second set to beat Gonzalez, but the Japanese native ultimately won 6-3, 7-5.

Second-seeded David Ferrer dealt Igor Sijsling a 6-3, 7-6 (7-4) loss to advance to the second round.

No. 3 seed Grigor Dimitrov beat Filip Krajinovic 6-3, 5-7, 6-0, while sixth- seeded Ivo Karlovic grabbed a 6-4, 3-6, 6-2 win over Russian Teymuraz Gabashvili.

American Ryan Harrison was up in the third set against compatriot Donald Young before Young retired. Bernard Tomic lost the first set in his match against Adrian Mannarino, but he took the final two for a 3-6, 6-4, 6-4 win.

In other action, Yen-Hsun Lu defeated Victor Estrella Burgos 6-2, 7-5; Austrian Andreas Haider-Maurer downed Robin Haase of the Netherlands 6-3, 2-6, 6-2; Steve Johnson cruised past Ivan Dodig 6-4, 6-4; and Viktor Troicki managed his way past Daniel Garza 6-4, 6-3.

The 2015 Acapulco champ will claim $343,000.