BY THE numbers, Essendon stalwart Jobe Watson enters the Bombers' season-shaping clash against Collingwood in fine fettle.

But assistant coach Guy McKenna doesn't care for the numbers. He's more interested in Watson's feet.

"Jobe started the season on his heels a little bit," McKenna said.

"He is now starting to roll up onto the balls of his feet and he's starting to get onto his toes now, which is good.

"We know he's not Carl Lewis or Usain Bolt. But he is certainly starting to run across the ground better which can only help grow his game outside the stoppages."

Watson is averaging 25.2 disposals a game on return after being banned for last season as a result of his club's 2012 supplements scandal.

In five of his past six games, the veteran has collected 27 or more disposals - and McKenna said such output would be vital against the Magpies.

Saturday's MCG fixture between the arch rivals could define the season of both clubs.

Essendon (11th spot, six wins, eight losses) have lost four of their past five matches, albeit by an average margin of just 10 points.

Another loss would likely put them three wins outside the top eight with just seven games remaining.

Collingwood (five wins, nine losses) languish in 15th place after three consecutive losses, with defeat surely bringing to an end their remote finals prospects.

The Magpies have recalled swingman Ben Reid, a week after his shock omission, while defender Travis Varcoe is back from a hamstring injury and Josh Smith is also included.

But Darcy Moore (hamstring) and Tom Phillips (illness) are significant outs and Jackson Ramsay was dropped.

The Bombers brought back David Myers and axed Kyle Langford.

"Like it generally is, it's going to be won or lost in the midfield," McKenna said.

"When you're consistently winning the ball in the midfield, the contested ball, the clearances, you tend to win the inside-50 count.

"You have got win that battle. And if you do, it gives you a better chance of winning."