MELBOURNE (REUTERS) - The coach of Ana Ivanovic, and father-in-law of men's world No. 2 Andy Murray, collapsed in the stands at Rod Laver Arena during the Serb's third-round clash with American Madison Keys on Saturday, causing play to be suspended indefinitely.

A Reuters witness said that Nigel Sears, father of Murray's wife Kim, was conscious and appeared to be speaking to medical staff as they treated him before he was taken out of the stadium on a stretcher and then to hospital.

Ivanovic was leading 1-0 in the second set after taking the first 6-4, when play was halted as the players went to change ends.

Television microphones picked up her talking to chair umpire Felix Torralba that she thought the person being treated was her coach.

Murray, oblivious to the development, was playing Portugal's Joao Sousa on Margaret Court Arena.

It is the second time this tournament that one of Ivanovic's matches had been suspended due to an incident in the stands.

Her second-round match against Anastasija Sevastova was held up for 26 minutes when a woman fell in the stands at the same show court.