ADELAIDE key forward Josh Jenkins looks set to finish his AFL career with the Crows after putting pen to paper on a five-year contract extension.

Jenkins, 27, turned down a lucrative offer from the struggling Brisbane Lions to re-sign with the second-placed Crows in what is a massive boost ahead of Saturday night's blockbuster with Geelong at Simonds Stadium.

AFL.com.au understands his new contract is in the region of $550,000 per season.

The Crows can now avoid speculation about Jenkins' future for the final six rounds of the competition and put all their energy into securing the club's third premiership and first since 1998.

"I mentioned from the very start that I was keen to stay in Adelaide. I always had that intention," Jenkins told afc.com.au.

"I really believe in what we've built here and what we can continue to achieve going forward.

"The club has created an environment where you can get the best out of yourself and more importantly players, coaches and staff have bought into the team-first culture.

"We're all here for success.

"The reason I've been more than happy to commit for so long is because I don't think we're far away from that.

"With the demographic of the group, what we've been through and how we've become so close, and with the team playing such good football, I think we can sustain that."

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Jenkins is fourth in the race for the Coleman Medal with 44 goals this season, equal with teammate Eddie Betts.

Jenkins needs three more goals to better his career-high of 46 goals in a season, set last year.

He is the second Crows player to be signed until 2021 along with full-back Daniel Talia, who penned a four-year extension earlier this year.

Crows captain Taylor Walker and midfield dynamo Rory Sloane are both signed until 2018, as is ruckman Sam Jacobs.

Jenkins was selected by Essendon with the 12th pick of the 2010 rookie draft, but he didn't play any games with the Bombers before being traded to the Crows the following year.

He is confident he can continue to contribute to the Crows well into his 30s.

"Hopefully, someone like (20-year-old) Harry Dear comes along and kicks me out (of the team) at some stage and the club continues to move forward," Jenkins said.

"I had a late start to footy … and we've seen that (mature-age recruits like) Ian Callinan and James Podsiadly have been able to play well after 30 because they've looked after themselves.

"Hopefully, I'm able to do the same."

Crows coach Don Pyke is impressed with Jenkins's work ethic and leadership.

"We are rapt Josh has decided to stay as his form and progress this season has been fantastic," Pyke said.

"Josh's talent as a forward has been on show for everyone to see, but equally important is the work he has done to build and evolve his leadership qualities both on and off the field.

"He provides real flexibility and balance to our line-up, can play minutes in the ruck and is always keen to learn and improve his game."