Key defender Brian Lake continues to come under strong criticism as he and the Western Bulldogs struggle for form this AFL season.

Former Sydney coach Paul Roos said on Monday that the two-time All Australian was not prepared well enough for matches.

Lake and key forward Barry Hall were notably out of form on Sunday as Hawthorn easily beat the Bulldogs.

That left the `Dogs with only three wins from nine matches in a season where they want to contend for the premiership.

"If I was a member of the Bulldogs, I'd be asking some serious questions of Brian Lake," Roos told the Fox Sports program On The Couch.

"He looked all at sea ... marking contests that he would normally take, he fumbled.

"I just think, if you're a professional AFL footballer you've got to present better than that."

Lake had off-season surgery and has notably struggled so far this season.

But Roos said it looked like he needed to train better.

"At some point it's incumbent on Brian Lake to train hard to present himself well for the weekend," Roos said.

"For some reason he hasn't been able to do that."

Roos coached Hall at Sydney before the key forward went to the Bulldogs and said he still could contribute to the Bulldogs.

"You can still worry about the future if he's not playing as well," Roos said.

"You can still set your team up - he is smart enough to know when his time is up."

Brought to you by AAP © 2024 AAP