Konta battles through to US Open second round

"I'd lost my last two matches to her and expected a long tough match," said Konta.

"That's what it was and I'm pleased how I managed to adapt."

Konta, beaten in the first round here for the last two years, elected to receive and promptly broke her opponent's serve, aided with a couple of double-faults from Kasatkina.

Konta's solid service games kept her out of trouble in the opening set while she pounced upon Kasatkina's second serve at every opportunity, two further breaks wrapping it up in just 23 minutes.

Kasatkina is a better player than that, having been in the top 10 not so long ago, and she began to show it in the second set.

Having finally found her range, she came up with a couple of confident holds followed by a break of the Konta serve for 3-2.

The pressure was building on Konta, who was fuming after a Kasatkina forehand was called out only for the umpire to overrule and award the point to the Russian.

She reached boiling point moments later when her own forehand was called out and overruled, only for the point to be replayed.

Konta regained her composure, though, and secured the crucial break to lead 4-1 in the decider before completing an impressive victory.

The 28-year-old is already Britain's sole representative in the women's singles in New York after Harriet Dart tumbled out.

Londoner Dart, who came through three rounds of qualifying to reach the main draw for the first time, lost 6-3 6-1 to Romanian Ana Bogdan.