MELBOURNE coach Paul Roos says even the Demons coaching group didn't know if forward Jack Watts would realise his potential. 

Watts has long been criticised since being drafted with the first pick in 2008. 

Now into his eighth season, the 25-year-old kicked four first-half goals against Collingwood on Sunday afternoon at the MCG to help beat the Pies.

Click here to watch Paul Roos' full press conference

It was a strong contrast to Watts' debut against Collingwood in 2009 when he was pushed around by a Magpie defence keen to make a statement against the gangly teenager. 

The forward has nine goals through four rounds this year and is an integral part of the Demons' attack. 

"He's much maligned. Even we get caught up in it (the criticism) as well," Roos said after the impressive 35-point win. 

"We were always confident that he (Watts) had talent, and when he plays the way we want him to play, he's an effective player. 

"Last year, we felt he had a really good season, but he would play one bad one and everyone jumps on him.

"He had a poor game against Essendon (in round two) but his body of work through the NAB Challenge and round one meant people laid off him a bit.

"He responded last week and he responded again (today)."

Early blitz sees Demons cruise past Magpies

Watts kicked three goals against North Melbourne in round three. 

Melbourne's starts had been slow prior to playing Collingwood. The Demons trailed by six goals at the first break against the Kangaroos (before eventually losing by five points) and fell behind Essendon early in their round two clash, before going down by 13 points. It was a trend the coach was delighted to rectify.

"We've been starting not that well," Roos said.

"When one of your key forwards (Watts) takes a mark and kicks a goal, it gets you off to a really good start. 

"We're like everyone – we need our talented players playing well because we have got a lot of young players. 

"It's four weeks in and we hope he continues to play like that, because he's obviously really important."

Watts is out of contract at the end of the season and would be a restricted free agent.

Roos said he wasn't confident his team would deliver such a strong performance against the Pies considering the personnel missing.

"It's been two really good weeks, probably the best two we've had back-to-back, even though we lost last week (against North Melbourne)," he said.

"We're starting to see the type of footy we want to play more regularly.

"Going into the game, you're nervous when your best and fairest winner (the suspended Bernie Vince) is sitting in the coach's box. 

"Jeffy (Garlett) pulls out because he couldn't train – there's two high quality players (out) that are experienced.

That pair was replaced by Angus Brayshaw and Jayden Hunt. Hunt was on debut while Brayshaw was playing just his 23rd game.

Melbourne face Richmond next Sunday night at the MCG. A win would have the club sitting 3-2 and the Demons haven't started as season that well since 2010.