Grigor Dimitrov's promising Wimbledon upset bid against Jannik Sinner ends in heartbreaking injury retirement

Grigor Dimitrov was one set away from upsetting Wimbledon’s No. 1-seeded men’s singles player, Jannik Sinner, on Monday. 

But an untimely injury changed all of that.

Dimitrov had to retire from the match in the Round of 16 due to an apparent pectoral injury despite owning a 6-3, 7-5, 2-2 lead over Sinner. 

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In turn, Sinner is heading to the Wimbledon quarterfinals. 

During a serve, Dimitrov immediately fell on the grass court in pain, grabbing at his right pec.