In the opening game, the 24-year-old Kazakh player broke the Ukrainian to love and easily won the first set.
The 2022 Wimbledon champion Rybakina broke early in the second set, and Kostyuk was unable to recover.
Following victories in Brisbane in January and Abu Dhabi the following month, Rybakina now has a victory.
With an outstanding victory over Iga Swiatek, the two-time defending champion and top seed in the world, on Saturday, she secured her spot in the championship match.
The one opportunity Kostyuk had to rally was in the second set when, trailing 3-2, she forced three break points. However, she was unable to capitalize on the opportunity and appeared irate, almost to the point of tears.
Naturally, I want to congratulate Marta. This has been a wonderful tournament, and you’ve played some amazing matches. I hope we get to play many more finals together, Rybakina remarked.
