Anisimova came into the match having won six of their previous 10 meetings, although they had met at each of the last three Grand Slams, with Sabalenka winning this head-to-head meeting two wins to one.
She won in four straight sets in the fourth round of the French Open and in the final of the US Open, while Anisimova won in three sets in the semi-finals of Wimbledon.
Their semi-final in Riyadh promised a lot – and delivered results.
The first two games took 18 minutes. Anisimova saved three break points to hold on in the first match, then Sabalenka fought back from 0-40 down to do the same.
An hour passed on the game clock when Sabalenka finally won the first set.
Anisimova, who failed to win the first set in four matches on her WTA Finals debut, responded brilliantly to take a 4-0 lead in the second match to level the match.
In the decider, Sabalenka's winning backhand return in the seventh game sealed the decisive break of serve, and a warm embrace developed between the two players at goal as Anisimova sent her forehand wide.
“I told Amanda she should be proud of her season – she’s played incredible tennis all season and this is just the beginning,” Sabalenka said.
“I know she's probably disappointed, but there's still a lot of things to look forward to.”
