MASON, Ohio (AP) Mardy Fish surprised even himself.

Fish opened the next-to-last tournament of his career with a convincing 6-2, 6-2 victory over 20th-ranked Viktor Troicki in the first round of the Western & Southern Open on Monday.

''I was a little surprised at my level,'' Fish said. ''I hadn't practiced a ton or particularly well for a little while. I was struggling with my serve.

''A friend of mine came in a couple days and helped, but it was still sort of a struggle even yesterday to sort of find my serve and stuff. I was obviously real happy with the level.''

Fish, a wild card who plans to retire after the U.S. Open, next faces second-ranked Andy Murray. It was Fish's first singles victory on tour since Aug. 18, 2013, against Evgeny Donskoy at Winston-Salem.

Two seeded players lost in the first round. Jerzy Janowicz surprised 14th-seeded Gael Monfils 6-4, 7-5, and Ivo Karlovic improved to 3-1 in his career against 10th-seeded Gilles Simon with a 6-4, 6-7 (3), 6-3 win.

Jack Sock rolled to a 6-1, 6-2 win over wild card Bjorn Fratangelo, and Roberto Bautista Agut beat Pablo Cuevas 6-3, 6-4 in two late matches.

The match between wild card Jared Donaldson and qualifier Nicolas Mahut was suspended because there were no lights on their court. Donaldson leads 7-5, 6-7 (2), 4-1 in the third set.

Venus Williams had to wait out a rain delay of more than 2 hours before beating Zarina Diyas 7-6 (6), 6-4.

Two women's qualifiers advanced in matches delayed twice by subsequent showers. Timea Babos outlasted Samantha Stosur 7-6 (6), 4-6, 7-5, and Yaroslava Shvedova knocked off Wimbledon finalist Garbine Muguruza 6-4, 7-6 (0).

No. 12 seed Timea Bacsinszky also lost, falling to Madison Keys 6-4, 6-3 in a matchup of Wimbledon quarterfinalists.

Keys overcame 26 unforced errors - 17 in the first set - to advance.

''I didn't know I had that many, to be honest,'' she said. ''The way I play my game, I'm always going to have more unforced errors, but I'm going to have more winners, too.''

Play was interrupted three times for a total delay of just under three hours, according to tournament officials.

Fifteenth-seeded Andrea Petkovic moved on with a 6-4, 6-2 win over qualifier Julia Goerges, and 14th-seeded Elina Svitolina shook off determined wild card Alison Riske 6-2, 4-6, 6-0. Tsvelana Pironkova advanced with a 7-5, 3-6, 6-1 win over qualifier Lucie Hradecka.

Irina-Carmelia Begu got past Alize Cornet 6-4, 6-4 in the last singles match of the night.

In other men's action Monday, No. 13 seed David Goffin rallied past qualifier Yen-Hsun Lu 5-7, 6-3, 6-4. Joao Sousa defeated Philipp Kohlschreiber 6-2, 6-7 (5), 6-2, and Bernard Tomic beat Sergiy Stakhovsky 6-4, 6-3. Gilles Mueller eliminated lucky loser Benoit Paire 7-6 (5), 7-6 (6), and Thomaz Bellucci topped Jiri Vesely 7-6 (5), 6-2.

In the last men's match of the day, qualifier Thanasi Kokkinakis rallied to beat Fabio Fognini 4-6, 6-2, 6-3.

In more women's first-round play, Varvara Lepchenko edged Barbora Strycova 2-6, 7-5, 7-6 (6), and Wimbledon quarterfinalist CoCo Vandeweghe cruised past qualifier Yulia Putintseva 7-5, 6-2. Jelena Jankovic advanced with a 4-6, 6-4, 6-2 win over Madison Brengle, and Karin Knapp defeated Ana Konjuh 7-5, 6-2.

Vandeweghe met Putintseva for the first time since May 2013, when Vandeweghe claimed on Twitter that Putintseva and her father insulted her after the match.

''The win speaks for itself,'' Vandeweghe said. ''The scoreline speaks for itself. That's all I have to say.''