Kunitsyn won his first match of the year after consecutive first-round losses at Brisbane, Auckland, the Australian Open and San Jose.
"I've been playing good tennis since the Australian Open,'' Kunitsyn said. "It's unfortunate I couldn't get a win. I knew it was just a matter of time. My game has been feeling better week after week.''
Kunitsyn's first win of the year came against his longtime friend and Davis Cup teammate.
"It's never nice beating your best friend,'' Kunitsyn said. "It's not a good feeling.''
Andreev, ranked No. 22, is coming off the best season of his career. He ended the year ranked in the top 20 for the first time and won a personal-best 43 matches.
"He overpowered me in the first set, but I turned it around in the second set,'' Kunitsyn said. "I started serving better.''
Kunitsyn did not face a break point in the second and third sets.
In women's play, Michaella Krajicek, sister of former Wimbledon champion Richard Krajicek, knocked off No. 7 seed Alla Kudryavtseva, 6-1, 6-4, and 16-year-old Michelle Larcherde Brito, a wild card entry, defeated 2006 Memphis champion Sofia Arvidsson, 6-2, 6-0.
Women's seeds advancing Monday were No. 2 Victoria Azarenka, who beat American Varvara Lepchenko, 6-2, 6-2; No. 3 Lucie Safarova, who beat Melanie South, 6-2, 6-2; No. 4 Anne Keothavong, who defeated Maria Elena Camerin, 3-6, 6-3, 6-1, and No. 8 Pauline Parmentier, who beat Julie Coin, 7-6 (6), 4-6, 6-1.
In men's play, Andreev was the only seed in action Monday. In other matches, two qualifiers advanced. Australian Chris Guccione won 49 of his 51 first-serve points and fired 19 aces to defeat veteran Vince Spadea, 7-6 (1), 7-6 (5), and Israel's Dudi Sela beat Bobby Reynolds, 7-6 (4), 6-2.
Afterward, Sela addressed the decision by the United Arab Emirates to deny Israeli women's player Shahar Peer a visa allowing her to play in this week's Dubai Tennis Championships.
"I think it's a pity,'' Sela said. "I think all players (who are eligible) should have the same opportunity.''
In an exhibition match, former world No. 1 and 14-time Grand Slam champion Pete Sampras lost to Lleyton Hewitt, 7-5, 6-4. Hewitt, also a former world No. 1, is coming back from a left hip injury that has dropped his ranking to 103 and will play No. 3 seed James Blake in a first-round match Wednesday.
No. 6 seed Andreev ousted
No. 6 seed Andreev ousted
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