Photo/IllutrationKei Nishikori returns a shot to Spain's Fernando Verdasco during their match at the Gerry Weber Open ATP tennis tournament in Halle, Germany, on June 20. (dpa via AP)

HALLE, Germany--Kei Nishikori toiled for his opening grass-court victory of the year, beating Fernando Verdasco 6-7 (7), 6-3, 6-4 in the first round of the Gerry Weber Open on Tuesday.

The third-seeded Japanese player saved nine of the 10 break points he faced to win in under 2 1/2 hours for a second-round meeting against Karen Khachanov of Russia.

Khachanov defeated Gilles Simon of France 6-2, 6-7 (2), 6-3.

The fourth-seeded Alexander Zverev had no problems against Paolo Lorenzi, winning 6-3, 6-2.

German veteran Tommy Haas' final appearance at the tournament was brief as he lost to Bernard Tomic 6-4, 6-4. The 39-year-old Haas, who made his Halle debut 20 years ago and won it twice, plans to retire at the end of the season.

The seventh-seeded Roberto Bautista Agut beat Carlos Berlocq 6-0, 4-6, 6-2, Robin Haase defeated David Ferrer 3-6, 7-5, 6-3 and Germany's Mischa Zverev beat Slovakian qualifier Lukas Lacko 6-4, 6-4.

Also, Florian Mayer defeated Benoit Paire 6-0, 6-4.

Eight-time champion Roger Federer was to open later Tuesday against lucky loser Yuichi Sugita of Japan. Original opponent Lu Yen-hsun was forced to withdraw with a right arm injury.