Anisimova went into the match having won six of their previous 10 meetings, though they have met at each of the past three Grand Slams and Sabalenka edged that particular head-to-head two wins to one.
She prevailed in straight sets in the French Open fourth round and the US Open final, while Anisimova was victorious over three sets in their Wimbledon semi-final.
Their semi-final in Riyadh promised much – and delivered.
The first two games took 18 minutes to complete. Anisimova saved three break points to hold in the opener, then Sabalenka fought back from 0-40 down to do likewise.
The match clock had just ticked past an hour when Sabalenka eventually clinched the first set.
Anisimova, who failed to win the opening set in all four of her matches during her WTA Finals debut, responded brilliantly by racing into a 4-0 lead in the second and levelling the contest.
In a tight decider, Sabalenka’s backhand return winner to settle the seventh game sealed a decisive break of serve, and there was a warm embrace between the two players at the net when Anisimova sent a forehand wide on match point.
“I told Amanda that she should be proud of her season – she’s played incredible tennis for the whole season and it’s just the beginning,” said Sabalenka.
“I know she’s probably disappointed but there are many more things coming her way.”