Andy Murray's father-in-law Nigel Sears is being treated in hospital but says he is "feeling fine" after collapsing at the Australian Open.
Sears, 58, coaches Ana Ivanovic and was watching her match with Madison Keys on Rod Laver Arena. The match was suspended for an hour before resuming.
Murray was not made aware of what had happened as he was playing Portugal's Joao Sousa at the time.
Sears later told the BBC he hoped to be released from hospital on Sunday.
Immediately after his four-set win, Andy Murray left the venue, along with his mother Judy, to visit his father-in-law in hospital.
Sears' daughter Kim is not in Melbourne in support of Murray as she awaits the birth of their first child in a few weeks' time.
Ivanovic, the 20th seed, was a set up when the incident occurred and went on to lose 4-6 6-4 6-4 to 15th seed Keys.
Sears is in his second spell working with Ivanovic after he was reappointed the Serb's coach in July last year.
He has previously worked with Daniela Hantuchova and Amanda Coetzer and was also captain of the British Fed Cup team.
It is the second time this week 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 showcourt.