Scottish tennis champion Andy Murray has added to the unpaid ball kid debate at the Australian Open after weary-eyed children were forced to work until after 4am without pay on Thursday.

The ball kids at the Australian Open have to dodge serves travelling at over 200km/h and endure the searing Melbourne heat without being earning a single cent, despite their counterparts at other grand slam events being paid.

Now they can add all-nighters to their workload. 

Murray, 35, turned back the clock to dig deep and find some of his best form against Australian Thanasi Kokkinakis. 

The Brit was down two sets and staring down the barrel of a break point in the third set before rallying to complete a memorable five-set victory against the local hope.

The drawn out match didn't even start until around 11pm AEDT and Murray said that was unfair on the unpaid child workers.  

'If my child was a ball kid for a tournament, they're coming home at 5am in the morning, as a parent, I'm snapping at that,' Murray said.

'It's not beneficial for them. It's not beneficial for the umpires, the officials. I don't think it's amazing for the fans. It's not good for the players.

'We talk about it all the time. It's been spoken about for years. When you start the night matches late and have conditions like that, these things are going to happen.'

Many fans agreed that matches at the Australian Open should start earlier.

'Probably the biggest match of the night and they start it at 10pm. The big matches like this should be moved to the 7pm start times.' one fan posted.

'It's ridiculous it even started around 10pm or whatever it was poor decision Tennis Australia! Have a reserve day for delays, it's not rocket science,' said another.

'Tired … big games should start earlier. The organisers know which games could go on and on. Great match this one though,' added another. 

On Friday morning, a GoFundMe page was set up with the intention of raising $25,000 to be sent directly to Tennis Australia for distribution to the ball kids.  

While there were many fans who sympathised with the youngsters, there were others who said late nights were part of the experience of getting to interact with the biggest stars of the sport.

'If I was a ball kid back in the day, I would've loved front row seats to an awesome match that went for 6 hours. Wouldn't even want a cent for it. What a story to tell later on to your mates back at school after school holidays.' one fan replied.

Despite the calls from fans and some players including Murray to alter the schedule, Tennis Australia boss Craig Tilley said that was unlikely to happen.

'At this point, there's no need to alter the schedule,' he said on The Today Show.

'We will always look at it, when we do the (tournament) debrief – like we do every year.

'But at this point, at what it is, we've got to fit those matches in the 14 days, so you don't have many options.'