Mackenzie McDonald, Donna Vekic and Dusan Lajovic also threw in the towel Thursday at the Western & Southern Open.

The Top 4, however, are all safely through to the round of 16 at the Western & Southern Open.

There won't be a rerun of the last weekend's friendly Bastad final between the top two seeds.

Rafael Nadal called his rival's 23 major titles "a number that just a few years back was impossible to think about," as Genie Bouchard hailed Djokovic as "the undisputed GOAT".

Fresh off his first ATP title since 2019, Lajovic kept the milestones coming with his opening victory in Madrid.

Even if Carlos Alcaraz wins the Masters 1000 event, Djokovic will still keep the top spot by five ranking points.

The 22-time major champion went just 1 for 16 on his break point chances in defeat Friday.

Baez enters this match as a heavy favorite, but Lajovic will make him earn his spot in the next round.

Dusan Lajovic spoiled Daniil Medvedev's Top 3 debut on Wednesday after ousting the top seed, 7-6 (4), 6-4, at the ABN AMRO World Tennis Tournament. Alexander Bublik also pulled off a Top 10 win, eliminating world No. 7 Alexander Zverev, 7-5, 6-3.

In his first match of the 2021 season, the No. 1-ranked Serb beat the Canadian No. 1 in two tight sets to extend his winning streak in Australia to 21 matches. He then took the court again to lead Serbia to a 2-1 victory in the tie.