Grigor Dimitrov overcame Reilly Opelka’s huge serve, to beat the the American 6-3, 6-4 to advance to the fourth round in Indian Wells on Monday.

In windy conditions Dimitrov found the right distance to tackle Opelka’s serve, countering his heigh – 6ft 11 – to take the match in 74 minutes.

Dimitrov, who did not face a break point against Opelka, will face either No.1 seed Daniil Medvedev or Hamburg finalist Filip Krajinovic in the last 16.

Meanwhile, American veteran John Isner has withdrawn from the event because his wife Madison is expecting their third child.

Isner was 20 minutes away from taking to the court for a doubles match when he received a call from his wife that their baby was coming early.

“Pretty eventful day,” Isner said in a statement. “I need to go home to be with the family, that is what my duty is right now. Much more important than tennis.”