By Shrivathsa Sridhar LONDON (Reuters) -Top seed Jannik Sinner struggled with an elbow problem and was given an almighty scare before advancing to the quarter-finals of Wimbledon after a cruel twist of fate for his 19th-seeded opponent Grigor Dimitrov who retired injured while two sets up.

In a video of the moment, it looked as though the 34-year-old Dimitrov injured a pectoral muscle on a volley. Almost immediately after the hit, he fell to the ground, clutching the right side of his chest in pain.

Jannik Sinner reached the quarterfinals at the Wimbledon Championships in a completely unexpected way. The world No. 1 was considered a clear favorite against Bulgarian veteran Grigor Dimitrov on Centre Court,