JARROD Witts believes his ruck battle against Fremantle's Aaron Sandilands in Perth on Thursday night gives him the opportunity to stamp himself as Collingwood's No.1 big man. 

With Brodie Grundy still in a neck brace and a couple of weeks from returning to the field after a training mishap earlier this month, Witts must carry the Pies' ruck burden.

Tasks do not come much bigger than taking on the Fremantle giant, who ranks second in the AFL in hit-outs per game in 2015.

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"I played against (Shane) Mumford last week (against Greater Western Sydney in round 11) and he was a quality opponent," Witts told AFL.com.au.

"Now I've got another chance to come up against the best again this week. It's a great opportunity for me to put my hand up as the No.1 ruckman in this team."

Sandilands is pivotal to the way Fremantle plays.

The 211cm, 119kg ruckman wins hit-outs 65 per cent of the time and is ranked No.1 in the competition in this category in 2015.

The four-time All Australian's hit-outs also find the target an AFL-high 20 per cent of the time.

When Sandilands is at his most dominant, Fremantle midfielders Nat Fyfe, David Mundy, Lachie Neale and Stephen Hill thrive at the stoppages.

What makes Fremantle's on-ballers so dangerous is their ability to exit stoppages on the move and create forward momentum when the ball is up for grabs.

Witts, who stands 209cm and 113kg, says his ability to contain Sandilands will be crucial if the Magpies are to inflict the Dockers' second loss of the season. 

"It's about nullifying his impact and not giving him the same looks every time," Witts said. 

"He uses his size really well. His tap work is second to none. It will be a big challenge, but I'm looking forward to it."

Magpies coach Nathan Buckley said the challenge of taking on Sandilands was not beyond the 22-year-old.

"If we had others, to be honest, we would put two rucks in," Buckley said.

"But we're really happy with Jarrod's ability to compete and contest, and Jesse (White)'s ability to support that.

"We can cover."

After a delayed start to the season due to off-season shoulder surgery, Witts believes he is starting to reach peak condition approaching his sixth game in 2015. 

"It took me a little longer than I was expecting," Witts said.

"I had a few hiccups along the way but the strength is there in my shoulder and I'm feeling more confident with it."

Buckley has stated his preference to have both Grundy and Witts in partnership in the ruck.

That suits Witts, who is averaging 21.8 hit-outs per game this season, just fine.

"We've probably played 15 or 20 games together now, so we're starting to understand how to work over an opponent," Witts said.

"It's going to progress the more we play together and for the betterment of the team we'll be able to have a lot more power at the contest and through the middle of the ground."