ESSENDON will inform the League by the end of the week how many more players it needs to recruit for the NAB Challenge after signing "in-principle agreements" with a handful of ex-AFL players.

Former St Kilda midfielder Clint Jones is one of a few players that recently left an AFL club to have visited the Bombers' headquarters this week.

Former Geelong tall Mitch Brown, ex-Melbourne midfielder James Magner and Coburg VFL defender Michael Hartley also underwent medical screening.

However, Hartley failed his medical test and won't be part of the Bombers' NAB Challenge squad.

SANFL pair Jared Petrenko and Mitch Clisby are also in their sights but it's been reported they are yet to fly to Melbourne to visit the club.

AFL football operations manager Mark Evans said the Bombers' recruitment process, which was outlined by the League last week, has "mostly gone OK to date".

"My understanding is Essendon have already got an in-principle agreement from half-a-dozen players and they may look to extend that by a few more this week," Evans said.

"They'll confirm with us by the end of this week how many players they think they need for the early part of the NAB Challenge."

Dyson Heppell's younger brother Aaron, highly-rated VFL ruckman Sam Tagliabue, former Lion James Polkinghorne and VFL Bomber Anthony Tipungwuti played in the Bombers' practice match on Friday.

Former Geelong player Jordan Schroder – another Essendon VFL listed player – is also in the mix for a spot as a replacement player.

"They've all been identified, so they were all pretty excited," Essendon high performance football manager Neil Craig told on Friday.

"They'll have a couple of weeks to impress at training to push their case to play in the NAB Challenge.

"It's a great opportunity for them. We appreciate what they're doing for our footy club.

"Our responsibility is to try to put out the most competitive side as we can against the AFL clubs. We owe that to the other teams in terms of their preparation."

The Bombers can use their VFL team's players for the NAB Challenge, as well as recruit any state league player.

They play their first NAB Challenge game on March 7 in Morwell, against St Kilda.

Meanwhile, Evans said the AFL wasn't expecting a resolution on the Anti-Doping Tribunal any time soon.

The tribunal heard the closing submissions of the players last Tuesday and is now considering the evidence.

"I'm assuming they'll tell us when they're very close," Evans said.

"Originally they said they may need towards a month so we're not expecting to hear anything immediately."

Twitter: @AFL_JenPhelan