In the second instalment of his comprehensive trade wrap on LIONS TV, Lions National Talent Manager Rob Kerr has heralded the acquisition of former Geelong ruckman Trent West, saying he will be vital to new coach Justin Leppitsch's game-plan.

The Lions traded pick 41, which was acquired as part of the Billy Longer trade with St Kilda, to secure the 26-year-old who played 54 matches with the Cats.   

"Justin's game-plan includes two ruckman so it was pretty critical that we bring someone in and there was the opportunity for Trent," Kerr told LIONS TV.

"Clearly we needed a ruckman given Billy Longer was leaving the club. And Trent was probably playing his best footy when he was playing that second ruck role.

"Brisbane was going to give him more of an opportunity to play senior football regularly."

The Lions tried to convince Longer to stay in Brisbane after Hawthorn traded with St Kilda for Ben McEvoy but were unsuccessful.

"After the McEvoy trade Billy had to reconsider his position," Kerr said.

"Justin, myself and Peter Schwab met with Billy and his manager and a number of players got in touch with Billy.

"I think the reality is he'd probably made up his mind.

"Even though he'd thought things through again, emotionally he'd committed to going back to Melbourne and when St Kilda came and offered him a home that was meeting his needs he was happy to go along with that."