Stephen Dank's relationship with criminals will be investigated by police after the controversial sports scientist was shot at his Ascot Vale home in Melbourne's north-west early on Saturday.

Serious Crime Response Team detectives are investigating after the 52-year-old's head was grazed when six shots were fired at the front of the Gillespie Avenue home at 2.20am.

Fairfax Media understands Dank was sitting in his downstairs lounge room at the time of the shooting and was injured by a bullet fragment.

Six shots were fired at the property from close range, including a shot into a sliding screen door that is believed to have been the bullet that injured Dank.

Two other shots were fired into a security door, one into a glass panel next to the door, one into an upstairs ensuite window that passed through a blind and into a wall and one that hit a balcony.

"I'm OK, I'm fine," a shaken Dank told Fairfax Media.

But Dank has failed to show up for a scheduled Saturday afternoon  speaking engagement at a South Bendigo Football club, notifying organisers he would not attend despite having vowed earlier in the day that he would proceed as planned.

The shots appear to have come from a single firearm and police will investigate CCTV from a nearby property in a bid to identify the gunman.

Another person in the house at the time of the incident, believed to be Dank's wife, escaped without injury.

Melbourne's criminal world was abuzz on Saturday morning with rumours Dank owed money to dangerous people.

Sources say Dank has been under substantial financial pressure since the failure of a string of lawsuits he brought against media organisations for defamation.

"He borrowed a lot of money to fund those lawsuits and you wouldn't say it was from a regular big four bank," one source said. Dank effectively lost the lawsuits and was ordered to pay costs.

Shane "Dr Ageless" Charter, who was involved along with Dank in the Essendon supplements scandal, told Fairfax Media Dank had angered a lot of people.

"Dank has a serious image problem. He's decimated two sporting codes, he's caught up in all kind of financial disputes and he's pissed off some (underworld figures) for other reasons."

"The bloke has done more (media) doorstops at his house that anyone else in Melbourne. He's not hard to find," said the biochemist, who has two convictions for drugs and steroids.

Dank told FOX Sports News that he has a black eye and a badly cut nose, after a bullet grazed the bridge of his nose in the early-Saturday shooting.

Former Adelaide Crows coach and media personality Graham Cornes said he had spoken to Dank after the shooting.

"I've spoken to Stephen Dank he feels it was an attempt to silence him from a speaking engagement ... he's angry," Cornes said."Dank feels it was an attempt to prevent him saying what he was going to say at a football lunch."

Country football club the South Bendigo Bloods had hired Dank to speak at a club luncheon on Saturday afternoon but Dank revealed he would not be attending, less than an hour before the event was to begin.

It is likely that police will focus their investigations on links between Dank and criminal elements.

Dank owns an anti-ageing clinic in Sydney where police believe he has established relationships with both legitimate businessmen in search of anti-ageing substances but also with prominent sports identities.

More worryingly, though, the elixirs of youth offered by Dank have attracted members of outlaw motorcycle gangs. It is believed those links will be a first port of call for detectives probing the overnight shooting.

Police are also checking claims that Dank has substantial debts over several business ventures in Victoria.

"There is a long list of people who hate him," a senior detective told Fairfax Media.

The high profile and notorious self-dubbed sports scientist lives a relatively quiet life in suburban Melbourne but his Sydney-based clinic remains a lucrative business and may have brought him into contact with associates who are dangerous to know .

"I have no idea what he does with all his money," a business associate said.

The property faces on to a local reserve where police spend Saturday morning searching for clues.

Serious Crime Response Team and Armed Crime Squad detectives spent the morning inside the home and speaking with neighbours.

The upstairs window at Stephen Dank's property.

Neighbour Dean said he was surprised by the shooting in the quiet street and that he had been asleep at the time.

"We've got dogs that would bark at the slightest noise and they didn't go off last night so whatever happened was pretty quiet," he said.

Dean said he knew Dank lived there but didn't know him well.

"He just keeps to himself, we see him a bit on the park, making some phone calls, but that's about it," he said.

Anyone with information about the shooting incident is urged to contact Crime Stoppers on 1800 333 000 or make a confidential report at www.crimestoppersvic.com.au

With Cameron Houston