A video has emerged of Elena Rybakina's physio Stefan Duell reacting hilariously to her 3 am win against Daria Kasatkina at the National Bank Canadian Open (Omnium Banque Nationale) in Montreal.

World No. 4 Rybakina underwent a tense match against tenth seed Kasatkina to progress through to the semi-finals at the WTA 1000 event. The match went on for nearly three and a half hours.

Both Rybakina and Kasatkina broke serve 10 times, but the 2022 Wimbledon champion saved a match point to prevail in three sets, 5-7, 7-5, 7-6 (8).

Perhaps one of the most invested people in the crowd was Rybakina's physio Duell, who didn't leave the Kazakhstani player's side once during the 3 hours and 27-minute-long match.

As play drew to a close, the victor was decided in a tiebreak, which Rybakina scraped through 10-8. As she scored the winning point, the camera captured Duell's hilarious reaction as he stood up and cheered, throwing his arms in the air with joy.

The Tennis Letter shared the clip on social media with the caption:

"This reaction by Elena Rybakina's physio after her 3 am win is hysterical.

"He sat in this seat for 3 hours and 27 minutes and did not leave Elena's side once.

"This is the look of a man who gets to go home," followed by a laugh-till-cry emoji.

Duell will probably be preparing for more long matches as Rybakina progresses through the tournament. The third seed will face Liudmila Samsonova, who defeated world No. 2 Aryna Sabalenka to go through, in her semi-final match.