Novak Djokovic has been knocked out in the second round of the Cincinnati Open by Thiago Agustin Tirante.

The third seed lost 2-6 6-4 6-4 in two hours and 44 minutes in his first match since losing in the Wimbledon quarter-finals to Jannik Sinner on July 10.

Djokovic looked to be on his way to victory following a comfortable first set, which he won after converting break points in the sixth and eighth games.

However, the Serbian faced much more resistance in the second as he successfully defended eight break points across his first three service games.

It would be ninth time lucky for Tirante, though, as the Argentine made a crucial breakthrough in the seventh game to force a decider.

And Tirante needed just one break again in the third, which he secured in the ninth game, before serving to love to clinch victory.

1 - In defeating Novak Djokovic, Thiago Agustin Tirante has claimed his first top-5 win of his career; it was the first time Djokovic lost to an Argentine player since Rio Olympics 2016 (V Juan Martin Del Potro). Strike. #CincyTennis | @CincyTennis @atptour pic.twitter.com/YWS4ghw3U9

— OptaAce (@OptaAce) August 15, 2026

Elsewhere, Flavio Cobolli booked his place in the third round with a 6-1 4-6 6-3 win over Miomir Kecmanovic.

He will be joined in the next round by Jakub Mensik, who defeated Mattia Bellucci 7-5 2-6 7-6 (7-5).

Tirante claims another giant-killing

Djokovic has won the most matches in ATP-1000 events since the format’s introduction in 1990 (420) and appeared in the most finals at the Cincinnati Open in the Open Era (eight – level with Roger Federer), so not many could have predicted this result.

It is the first time Djokovic has lost to an Argentine player since the 2016 Olympics (v Juan Martin Del Potro), ending a 22-match winning run against such opponents.

But causing an upset is nothing new for Tirante, who now holds a 4-1 record against top-10 ranked opponents.

This was his first win against an opponent ranked in the top five, while his 23 wins on the Tour this year are the most he has ever managed in a single season.