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Elena Rybakina has secured the WTA Year-End No. 1 Ranking for the first time in her career after defeating Kazakhstani compatriot Yulia Putintseva 6-2, 6-3 in the Toray Pan Pacific Open Tennis second round.

The No. 1 seed did not drop serve through the 70-minute contest, saving the only break point she faced with a hefty backhand in the final game. Rybakina, who ascended to the World No. 1 position for the first time after capturing her third Grand Slam trophy at the US Open in September, closed out victory in appropriate fashion -- with her sixth ace of the day.

"It's always difficult matches against Yulia," Rybakina said in her on-court interview.  "I was ready for longer rallies. She plays a lot of drop shots and changing the rhythm, so I was happy I stayed focused, stayed aggressive and a lot of things worked for me today.

"I think the closed roof a little bit also helped me. I like to play in these kind of conditions. The ball is flying a bit faster, generally I think the conditions suit me really well."

Rybakina extended her winning streak to five matches following her title run last week in Ningbo, her tour-leading fourth title of the season. In the Tokyo quarterfinals, she will face a rematch of the Ningbo final against Leylah Fernandez. The Canadian defeated No. 8 seed Elise Mertens 6-2, 7-6(8), holding off a late charge from the Belgian from 4-1 down in the second set. Fernandez had to save two set points in the tiebreak before reprising her Ningbo first-round win over Mertens.

Rybakina holds a 4-2 head-to-head advantage over Fernandez, including the last three meetings in a row. Her 6-2, 6-2 scoreline in the Ningbo final marked the fewest games she has conceded to Fernandez in any of their matches.