Kiki Bertens powered past Kazakh Elena Rybakina 6-1, 6-3 in the St Petersburg Ladies' Trophy final on Sunday to become the first woman in history to retain the title.
The world No. 8 converted four out of eight break points and saved all five on her serve to seal a 10th WTA singles title after 74 minutes on court.
After easing through the opening set by winning six straight games, Bertens had to stave off a spirited Rybakina early in the second, saving four break points in the first game.
She then broke for a decisive 3-1 lead and dropped only two more games to clinch victory in style.
The Dutchwoman improved her head-to-head record over Russian-born Rybakina to 2-0 with the win, having beaten the world No. 25 in the Rosmalen semifinals on grass last year.
Bertens was scheduled to take on 36-year-old former world No. 1 Kim Clijsters in the opening round of the Dubai Duty Free Tennis Championships on Monday, but pulled out of the tournament after reaching the final in St Petersburg.
Clijsters, making a return to professional tennis for the first time in seven years, will play Australian Open runnerup Garbine Muguruza instead, organisers said in a statement.
Elina Svitolina, Dubai champion in 2017 and 2018, will now face a qualifier or lucky loser instead of Muguruza.