Essendon coach Matthew Knights says his team will be disadvantaged to some degree for its clash with Fremantle at Subiaco on Sunday due to the 'intimate' knowledge that his Dockers counterpart Mark Harvey will have of many Bombers players.

Harvey was an assistant coach at Essendon for eight seasons under former Bombers boss Kevin Sheedy before crossing to Fremantle as an assistant in 2006 and Knights believes his familiarity with Essendon could play into the Dockers' hands.

"He knows our players intimately having been involved at the Essendon footy club for a long period, so I guess that's a plus for him from a coaching perspective," Knights conceded.

And Harvey isn't the only current member of the Fremantle family with strong Essendon links as former Bombers Dean Solomon, Mark Johnson and possibly Kepler Bradley look set to line-up against their old side this week.

However, Knights played down what kind of effect playing Essendon might have on the aforementioned trio.

"There's obviously an Essendon flavour over there but in saying that ... there's a lot of guys at our club that have got history with their players and their staff also so that is an impetus for us also to play strong footy," Knights affirmed.

Knights admitted that informing Johnson and Bradley that their services were no longer required with Essendon were some of the toughest moments of his fledgling coaching career.

"I went around to Mark's house, looked him in the eye and said, you know, this is the decision and these are the reasons why and it was tough because Mark had had a fantastic history at this football club and been a real warrior for the Essendon football club," the Bombers coach said.

Johnson will play his 200th match on Sunday and Knights said he was happy for the 30-year-old who played the first 194 of those matches with the Bombers.

"I think it's a great milestone, to play 200 games it means you've done a lot right throughout your career," he said.

In some bad news for Essendon, speedster Jason Winderlich will undergo surgery on a prolapsed disc in his back early next week and has been ruled out for the rest of the season.

"It's been quite frustrating because he's had a stellar pre-season and was really flying and then he hurt himself and then he got right and then he got a bit sore," said Knights.

"It's been a stop-start year for Jason so, you know, he's a very important player to our club so it is disappointing to have him out for the entire season but it's the best thing for his career."

And Knights hasn't closed the door entirely on the prospect of former West Coast champion Ben Cousins re-igniting his AFL career with Essendon next season.

"We're open-minded about adding to our young list, but whoever we added to our list would have to be able to fit the piece in the puzzle considering where we're taking our football club ... that player would have to fit the right demographic and fit a lot of criteria," he said.

Meanwhile, the AFL has cleared in-form Bombers ruckman David Hille of spitting at a fan during Essendon's 35-point victory over Carlton on Sunday.