(REUTERS) - Reaching top of the world seemed to agree with Angelique Kerber, who celebrated her ascension to world No. 1 with a 6-4, 6-3 win over Caroline Wozniacki on Thursday to advance to the US Open final.

The German left-hander was assured of becoming No. 1 when the new rankings come out on Monday after top-seeded American Serena Williams was defeated by Czech 10th seed Karolina Pliskova 6-2, 7-6(7-5) in the earlier semi-final.

Australian Open champion Kerber, who leads the WTA for most main draw match wins this season at 53-14, clinched victory with a backhand that actually landed just beyond the baseline but went unchallenged by former No. 1 Wozniacki of Denmark.

"It's just incredible. It's a great day," Kerber said on court.

"To be here in the final for the first time that means a lot. To be No. 1 in the world, it sounds amazing."

Kerber holds a narrow 4-3 career edge over Pliskova, but the big-serving Czech won their most recent encounter, in last month's Cincinnati final.