Top 5 Biggest Upsets at the National Bank Open 2026 So Far

The 2026 National Bank Open has already delivered unforgettable drama, stunning results, and unexpected exits. With several top stars either withdrawing or crashing out early, this year's ATP and WTA 1000 events have become some of the most unpredictable tournaments of the season.

Here are the five biggest upsets that have shaken the tournament so far.

1. Tallon Griekspoor Stuns Top Seed Alexander Zverev

The biggest surprise came when Tallon Griekspoor battled back to defeat World No. 3 Alexander Zverev 6-7(3), 6-2, 6-4 in Montreal.

Zverev entered the tournament as the top seed and one of the favorites for the title, but Griekspoor produced fearless tennis to eliminate the reigning Roland Garros champion in his opening match.

2. Daniil Medvedev Falls to Botic van de Zandschulp

Former US Open champion Daniil Medvedev also suffered a shocking early exit after losing in straight sets to fellow Dutchman Botic van de Zandschulp.

The upset removed another title contender and highlighted how unpredictable the Montreal draw had become.

3. Taylor Fritz's Washington Momentum Ends Immediately

Fresh off winning the Washington Open, many expected Taylor Fritz to carry that momentum into Montreal.

Instead, the American was defeated 7-5, 6-3 by Argentina's Thiago Agustin Tirante, ending his campaign at the very first hurdle just days after lifting a trophy.

4. Andrey Rublev Suffers Another Early Exit

Russian star Andrey Rublev failed to make an impact in Canada, joining the growing list of seeded players eliminated early.

His defeat further opened the draw and created opportunities for lower-ranked players to make deep runs in the tournament.

5. Caty McNally Shocks Wimbledon Champion Linda Noskova

One of the biggest surprises on the WTA side came when American Caty McNally defeated newly crowned Wimbledon champion Linda Noskova.

The result proved that the Toronto draw has been just as unpredictable as Montreal, with several unexpected winners emerging during the opening rounds.

Why Has the National Bank Open Been So Unpredictable?

Several factors have contributed to the shocking results:

• Injuries and withdrawals from top stars.
• Quick transition from Washington to Montreal and Toronto.
• Fatigue following Wimbledon.
• Rising confidence among the ATP and WTA Tour's next generation.

With many favorites already gone, the race for the National Bank Open title has become more open than anyone expected.

Final Thoughts

The 2026 National Bank Open has reminded tennis fans that rankings do not guarantee success. From Alexander Zverev's stunning defeat to Taylor Fritz's early exit and major surprises on the WTA Tour, the tournament has already produced some of the biggest stories of the hard-court season.

As the event continues, even more surprises could be waiting around the corner.