Flavio Cobolli and Taylor Fritz were both dumped out of the US Open in the third round on Saturday.

Fifth seed Cobolli lost 6-7 (4-7) 6-3 6-0 6-3 against 21-year-old Alexander Blockx in two hours and 45 minutes at Flushing Meadows.

Cobolli broke early on in the first set, and though Blockx eventually got proceedings back on serve, the Italian took the lead via the tie-break.

However, after saving three break points in the fifth game of the second set, the pressure told on Cobolli as Blockx secured back-to-back breaks to level the match.

And the Belgian followed up with a ruthless third, during which he lost just four points across the six games.

There was no way back for Cobolli in the fourth as he squandered four break points before Blockx booked his place in the last 16 with his first match point.

2 - Alexander Blockx is the second player from Belgium to defeat a top-5 seeded at the US Open in Men's Singles in the Open Era after Olivier Rochus in 2004 (vs Carlos Moya). Lion.#USOpen | @usopen @atptour

— OptaAce (@OptaAce) September 5, 2026

Fritz, meanwhile, was knocked out by Francisco Cerundolo despite winning the first two sets.

The home favourite lost 3-6 4-6 6-3 6-4 6-4 in three hours and 42 minutes, with Cerundolo now facing Blockx in the next round.

Blockx produces statement win

Blockx is the second player from Belgium to defeat a top-five seed at the US Open in men's singles in the Open Era, after Olivier Rochus in 2004 (vs Carlos Moya).

His performance in the third set was particularly impressive as he won 100% of his first-serve points (8/8) and 80% of his second-serve points (4/5).

Cerundolo, meanwhile, claimed his second career top-10 win at a grand slam event, with the other also coming against Fritz in the 2023 French Open.

Both Cobolli and Fritz will see this as a missed opportunity, with world number one Jannik Sinner missing out through injury and Novak Djokovic knocked out early on, too.