BEN Cousins will start his treatment for drug addiction in Malibu, California, as early as today.

He was putting on a brave face as he flew to Los Angeles from Sydney on Friday, but his demeanour suggested a man who was deep in thought about the journey ahead.

The West Coast star made no effort to hide his identity on the flight, and while has not spoken publicly, he chatted politely to airline staff and passengers.

He was booked in economy but was upgraded to business class.

He laughed and spoke freely on his mobile phone at Sydney airport and did a spot of shopping before leaving.

But he looked withdrawn and worn out from the events of the past two weeks and didn't sleep on the flight.

On the surface at least, he looks determined to overcome his addiction, believed to be to methamphetamine, head-on.

He went from Los Angeles airport to Venice Beach, where he shopped for clothes and music and enjoyed a relaxed lunch.

From there, he left for a secret location and is expected to check into a Malibu rehabilitation clinic as early as today, to begin the long road back to health and to restart his football career.

Cousins' father, Bryan, and minder, Ian Miller, are guiding the trip and met medical advisers when they arrived in the US. Cousins was expected to watch last night's West Coast-Sydney clash on the internet. He is booked to fly out of the US in a month but he is expected to stay longer.

Back in Australia, Collingwood president Eddie McGuire said he thinks the Eagle will struggle to play this year. "I think he'd be struggling, from anecdotal evidence," McGuire said.

"This isn't just, eat a bowl of nuts for a week and you'll be right," he told Southern Cross radio. "This is probably a lifetime journey now for Ben Cousins now to get off it."

But if Cousins' apparent determination is anything to go by, he may yet prove McGuire wrong and be back in Eagles colours.

Craig Hutchison travelled to Los Angeles with Ben Cousins on Friday.