Richmond defender Graham Polak remains in a medically induced coma in The Alfred hospital after being struck by a tram in Armadale late Saturday night.

A spokeswoman for the hospital said Polak remained in a serious but stable condition this morning.

Richmond media manager Judith Donnelly said media reports that Polak had emerged from a coma could not be confirmed at this stage but that he was responding to touch.

She said no further information could be provided until the club doctor emerged from a meeting with hospital medical staff.

Club doctor Greg Hickey yesterday said Polak had suffered bruising to the brain and his AFL career may be in doubt.

Further swelling in the days after the injury would increase the danger of permanent brain injury and the next 24 hours would be critical, Dr Hickey said yesterday.

Ms Donnelly said she believed the 24-year-old had been moved to the intensive care unit last night.

She was unable to provide specific details of Polak's condition, but could confirm he was "responding to touch".

Ms Donnelly said Polak's doctors were still talking to club doctors. The club is expected to make more information available at a media conference at 1pm today.

Polak's mother, Judy, and three brothers flew to Melbourne from his home state of Western Australia yesterday to join his partner, Alyce, at The Alfred.

Polak was struck in Armadale just hours after he played in the Tigers' 30-point loss to Carlton at the MCG. He was among players, staff, supporters and past players to attend a centenary function at the MCG on Saturday evening until about 8.30pm.

A club spokesperson said it was still unclear whether alcohol contributed to the accident about 11.30pm, after Polak had returned home to change his clothes.

"We're not completely sure if alcohol was a factor," the spokesperson said.

"It was more the staff and the former players that were drinking at the function beforehand because the boys had just suffered a pretty bad loss and were in a terrible mood.

"They were certainly not at the this function getting blind, I can assure you."

The Age believes most of the Tigers' players planned to kick off the mid-season break by meeting up again later on Saturday night.

After leaving his house, Polak was running for a taxi with teammates Cleve Hughes and Jordan McMahon across Dandenong Road, near its intersection with Orrong Road, when he was struck.

One teammate made it into the taxi, but Polak was hit by a number 64 tram travelling towards the city.

The impact with his head shattered the tram's front windscreen. But Polak, who is 196 centimetres tall, did not break any bones or suffer paralysis to his limbs.

Two ambulances and police arrived minutes later, and Polak was treated for 45 minutes before being made stable and transported to The Alfred.

Doctors put Polak in an induced coma because of bruising to his brain and were encouraged by some scans yesterday that showed there was no additional swelling since Saturday night.

Specialists had hoped to begin weaning Polak off the drugs that are keeping him unconscious yesterday but it proved too soon.

The club's doctor said Polak tried to wake up by himself yesterday morning, moving his arms and legs around on the bed.

"He was put in an induced coma and the reason for that was to shut the body down, shut the brain down and enable the hospital and the doctors to take control and monitor things carefully," Dr Hickey said.

Although Polak's condition has improved, he would be in hospital "for some time" and his AFL career was in doubt, he said.

"In terms of footy, it is unquestionable. He won't play this season - longer term beyond that, we'll just have to wait and see," Dr Hickey said.

"Probably the hardest thing to gauge at this stage is more his intellectual recovery, whether he will regain that - time will tell."

Polak was traded to Richmond from his home club of Fremantle at the end of the 2006 season. He played all 22 games for the Tigers last season and came seventh in its best and fairest competition.

Football manager Greg Miller said Polak's partner, Alyce, and his teammates were told of the accident on Saturday night, although some players did not know until yesterday morning.

Hughes and McMahon spent most of Saturday night at The Alfred, and other Tigers players, including captain Matthew Richardson, visited their injured teammate in hospital yesterday.

"It's a shock, but I don't know any details at this stage," Richardson said.

Victoria Police said it was unlikely the accident would result in any charges and it appeared Polak was distracted.

A spokesman for Yarra Trams said the tram driver was experienced and there was no suggestion he was speeding. "The tram driver was of course distraught after the incident and shaken and we offered him counselling but he declined it."