Svetlana Kuznetsova claimed a confidence-boosting win at the WTA Citi Open after earning her first hard-court victory in almost a year, while fifth seed Aleksandra Krunic was sent packing.

Kuznetsova was a class above as the Russian veteran eased past Kristie Ahn 6-2 6-1 in Washington on Monday.

Champion at the WTA International event in 2014, Kuznetsova had been hampered by a wrist injury that required surgery in the off-season.

It forced Kuznetsova – who had won just four of 10 matches heading into DC – to miss the Australian swing but the two-time grand slam winner did not face a break point as she progressed.

"I feel good physically - I think I wasn't ready and I came back too early [after wrist surgery] before, but now I took more time to prepare myself," said Kuznetsova, who needed four match points. "I trained in Miami for two weeks and I feel much better, faster and lighter on the court, which I hope will help my game."

Next up for Kuznetsova is either defending champion and fourth seed Ekaterina Makarova or Ana Bogdan.

That clash was postponed until Tuesday due to rain, which wreaked havoc in the United States, with Donna Vekic's match against Caroline Dolehide also rescheduled.

Belinda Bencic was leading 7-5 4-2 against Harriet Dart before bad weather halted proceedings.

Meanwhile, Krunic was no match for Katie Boulter in a shock 6-2 6-0 defeat, Andrea Petkovic was a 6-1 6-1 winner against Jamie Loeb, Alexandra Kiick beat Han Xinyun 6-2 6-3 and Fanny Stollar overcame Mayo Hibi 6-1 7-6 (8-6).