The 29-year-old American world No 3 dominated her Russian opponent from start to finish to claim a whirlwind 6-1, 6-0 triumph in just 49 minutes.

Fifteenth-seed Samsonova had battled through to the final after winning a gruelling three-set semifinal earlier Sunday against third seed Elena Rybakina in a match held over from Saturday due to torrential rain.

But the challenge of winning twice in one day ultimately proved too much for Samsonova, a rampant Pegula determined to claim her second elite WTA title after victory in Guadalajara last year.

The American, a quarterfinalist at the Australian Open and Wimbledon this year, was quickly into her groove with an early break in the opening set to go 3-1 up.

A superb crosscourt forehand put her 4-1 up before the visibly tired Samsonova was broken again in the sixth game to leave Pegula serving for the set.

Pegula, who defeated world No 1 Iga Swiatek in the semifinals on Saturday, slammed down an ace to move to set point, then bludgeoned another ace to close out the set.

Samsonova’s troubles continued in the second set, with a double fault gifting Pegula a break in the opening game.

From that point, it became simply a question of how quickly Pegula would wrap up victory, and the American was in no mood to drag out the second set.

A brilliant backhand crosscourt volley helped set up a break for a 3-0 lead and she then reeled off three more games to seal an emphatic win.