Cincinnati: No. 5 Holger Rune, No. 6 Jannik Sinner, No. 7 Casper Ruud, No. 8 Andrey Rublev lose on same day

The bottom half of the ATP's current Top 8, including Sunday’s Toronto champion Jannik Sinner, went down in the second round of the Western & Southern Open on Wednesday in Cincinnati. The rundown:

Mackenzie McDonald d. world No. 5 Holger Rune

In his Top 5 debut, Rune didn’t manage to finish his contest with the American. McDonald led 6-4, 2-0 when the No. 6 seed retired with a back injury. Assuming all is OK for the US Open, the Dane will head to New York seeking his first hard-court win since defeating Diego Schwartzman in the third round of Miami on March 26. A week after contesting his first Masters 1000 quarterfinal in Canada, McDonald is now a victory away from matching that effort.

Dusan Lajovic d. world No. 6 Jannik Sinner

Sinner came in on the back of his maiden Masters 1000 triumph. With a bye, he had two days in between to prepare for the transition at the Lindner Family Tennis Center. It didn’t go according to plan, as Dusan Lajovic won his fourth match in five days after coming through the qualifying rounds. The Serbian saved all five break points he faced to prevail, 6-4, 7-6 (4). Top-ranked American Taylor Fritz awaits in round three.

Max Purcell d. world No. 7 Casper Ruud

This was a match that was circled for an upset watch given Ruud’s lack of hard-court success in 2023. Coming into the contest, he was just 6-7 on the surface this year. With the confidence of winning two qualies matches and his main-draw opener, Purcell denied the Norwegian a decisive tiebreaker when he broke at 30 to end the clash. Worth noting: Ruud hasn’t won back-to-back matches on an outdoor hard-court since his 2022 US Open runner-up performance.

Emil Ruusuvuori d. world No. 8 Andrey Rublev

When Rublev returns to the Big Apple, he will have to shake off going winless at the Canada-Cincinnati double. And the latest blow will sting for a period: the No. 7 seed failed to serve out the first set, then missed two set points in dropping an opening tie-break and later was two points from winning. Instead, Ruusuvuori held from 0-30 down at 4-5 in the third set and Rublev couldn’t control his emotions in the ensuing tie-break. The final result: a 7 6 (10), 5-7, 7-6 (3) win for the Finn.

The Top 4 are all safely through, however. World No. 1 Carlos Alcaraz won a match that began Tuesday night and ran past 1 a.m., and then No. 2-ranked Novak Djokovic, No. 3-ranked Daniil Medvedev and No. 4-ranked Stefanos Tsitsipas each won their respective openers Wednesday.