Kasatkina was heading for heartbreak when she trailed 4-1 in the second set after losing the first, but the No.6 seed came roaring back to win a thriller 2-6 7-6 (7-3) 6-4 in Moscow.

The 21-year-old rallied from a set down to beat Alize Cornet in the second round after coach Philippe Dehaes instructed her to be "the Russian wall" and his stirring words were ringing in the home favourite's ears again.

Last year's runner-up was two games away from losing to the unseeded Tunisian when Dehaes marched on to deliver another plan of attack, which sparked a turnaround and will see her rise into the top 10 in the rankings for the first time.

Five of the next six games were won by Kasatkina and she edged a tie-break, then broke three times in the final set to claim the second WTA singles title of her career.

Kasatkina embraced her coach and said she had realised a dream by becoming the sixth Russian to win the event on home soil.

Jabeur wept as she was consoled by Kasatkina after ending the match clutching her thigh, the world No.101 having come so close to a maiden title.

Kasatkina and Jabeur delivered scintillating tennis of the highest order, with an array of stunning winners in a pulsating decider.