World No. 1 Jannik Sinner suffered a stunning second-round exit at the 2026 French Open after blowing a commanding lead against Argentina’s Juan Manuel Cerúndolo in sweltering Paris conditions on Thursday.
Sinner appeared to be cruising into the third round at Roland Garros after racing to a 6-3, 6-2 lead and moving within one game of victory at 5-1 in the third set. But the Italian star suddenly faded physically under the intense heat, allowing Cerúndolo to complete an extraordinary comeback and win 3-6, 2-6, 7-5, 6-1, 6-1.
The collapse sent shockwaves through Roland Garros, especially with Sinner entering the tournament as the overwhelming favorite following Sinner’s dominance this season and his pursuit of a career Grand Slam in Paris.
At one stage, Sinner looked untouchable. His heavy groundstrokes repeatedly pushed Cerúndolo behind the baseline as he dictated rallies with ease during the opening two sets. The Italian’s level was so high that many expected another routine straight-sets victory.
But everything changed midway through the third set.
When he returned, the momentum had completely shifted.
Cerúndolo sensed the opening immediately.
The Argentine, who had spent most of the match defending desperately, began extending rallies and forcing Sinner into longer exchanges. As temperatures climbed across Paris, Sinner’s movement deteriorated sharply while Cerúndolo grew in confidence.
The 24-year-old Argentine reeled off six consecutive games to steal the third set before dominating the fourth and fifth as Sinner’s resistance disappeared. ESPN later described it as the dramatic turnaround of the tournament so far.
Speaking after the defeat, Sinner admitted he had struggled physically throughout the afternoon.
“I started to feel very dizzy, very low on energy. I really couldn’t find any energy today,” Sinner said after the match.
Despite temperatures soaring in Paris, Sinner insisted the weather alone was not responsible for the defeat.
The upset is one of the most dramatic collapses of Sinner’s career and ends a remarkable run that included a historic Masters 1000 streak and a physically exhausting clay swing.
Questions about fatigue had already emerged after Sinner’s physically draining Rome campaign, while coach Patrick Mouratoglou had previously warned that physical exhaustion could become the only obstacle to the Italian’s dominance.
For Cerúndolo, the victory marks the biggest win of his career and his first appearance in the third round of a Grand Slam. The Argentine remained composed even after falling two sets behind and later admitted he felt sympathy for Sinner’s physical struggles while still embracing a career-defining moment.
The upset also reshapes the entire men’s bracket. With Carlos Alcaraz already sidelined before the tournament began, Sinner had been viewed as the clear favorite to capture his first Roland Garros title.
Now the tournament suddenly opens up for rivals including Novak Djokovic and Alexander Zverev. The result could become crucial in Novak Djokovic’s pursuit of another Grand Slam title.
The defeat also adds to a chaotic opening week in Paris after men’s draw already reshaped by Daniil Medvedev’s early exit.
Attention has also intensified around player welfare at Roland Garros amid extreme weather conditions and growing frustration over scheduling. The tournament had already been dealing with French Open tensions before the tournament even began.
The growing debate around player conditions is now expected to intensify after Sinner’s collapse under the Paris sun.
For Sinner, it was a brutal and unexpected end to a tournament many believed he was destined to win.
For Cerúndolo, it was the match of his life.
