Speaking on Melbourne radio SEN on Saturday morning, Pickering said a deal had been brokered on Thursday between the Bombers, the Eagles and St Kilda, before Hooker effectively put a stop to it.
NAB AFL National Draft order
"We actually had the deal done late on Thursday night, which involved Essendon and Cale Hooker," Pickering said.
"But Cale Hooker didn't want to leave the Bombers in the end, so that was the end of that deal.
"But it was going to be Hooker and (St Kilda's Jamie) Cripps (to West Coast), Essendon get picks 25 and 26 and Mitch Brown to St Kilda.
"But Cale Hooker was determined to stay at the Bombers and had a year to go on his contract, so that was the first snag."
It is understood West Coast put a three-year deal to Hooker, but the 24-year-old key defender, who played 17 matches for Essendon last season, turned it down.
Jury still out on Trade Period
The Eagles had said they weren't prepared to lose Brown under any circumstances, but it seems they would have brokered a deal, provided they received a replacement for their key defender.
"West Coast were pretty up front all the way through; they wanted cover for Mitch," Pickering said.
"They were happy to do the deal with Cale Hooker if he wanted to go back, just so they had the player there.
"But once they couldn't get the player, they were never going to do it for the pick, which was disappointing."
Trade wrap
Pickering's revelation contradicts comments earlier in the trade period from West Coast, which had told St Kilda that Brown - who is off contract at the end of 2013 - would not be traded under any circumstances.
Instead, according to the Eagles, they were hoping to extend Brown's contract.
"We'd definitely look at re-contracting him … there's always risk in 12 months' time if we haven't done that and we recognise that," Eagles list manager Craig Vozzo told Gillette AFL Trade Radio on October 16.
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"I think he sees there's opportunity here. We certainly have identified that for him."
East Fremantle product Cripps did ultimately join West Coast in the dying minutes of the trade period on Friday, along with pick No.46, with the Saints picking up selections 41 and 44 in next months' NAB AFL Draft.
James Dampney is a reporter for AFL.com.au. Follow him on Twitter: @AFL_JD
