Novak Djokovic's ATP Finals hopes suffer major blow after shock Basel Open exit

The German produced a superb performance to claim a 6-7 (4), 7-5, 7-6 (5) victory over the 24-time Grand Slam champion in a gruelling encounter lasting two hours and 36 minutes.

The Serbian initially appeared on course to extend his dominance, edging a closely contested opening set on a tiebreak. However, Struff fought back and broke Djokovic late in the second set to level the match.

Neither player was able to establish a decisive advantage in the final set, with both earning and saving break points before Struff held his nerve in another tiebreak to secure a memorable first victory over the former world number one.

The defeat is a significant setback for Djokovic's hopes of qualifying for next month's ATP Finals in Turin.

He currently sits 11th in the ATP Race with 2,890 points, 40 behind Australia's Alex de Minaur in 10th. Following Jannik Sinner's season-ending knee injury, the ninth position could also be enough to secure qualification, with Rafael Jodar currently occupying the final available spot on 3,184 points.

Djokovic could also slip further down the standings this week, with Taylor Fritz and Tommy Paul both having opportunities to overtake him with strong performances in Basel and Vienna respectively.

The Serbian's most realistic remaining opportunity to strengthen his qualification bid may now come at the Paris Masters, where he could need a deep run, potentially even the title, while also hoping his rivals drop points.

Djokovic had made qualifying for the season-ending championships one of his objectives, but his surprise defeat to Struff has left him with plenty of work to do.

For Struff, meanwhile, the reward is a place in the quarter-finals, where he will face Nuno Borges.

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