Jackson Trengove is officially a Western Bulldog after Port Adelaide elected not to match his free agency offer.

The Bulldogs lodged an offer for Trengove at League headquarters on Friday morning and Port announced several hours later it would not block the restricted free agent's path to the Whitten Oval. The Dogs have offered him a three-year deal. 

Trengove said he was excited to join the Bulldogs and would do his best to convince Port Adelaide teammate Jarman Impey to come along for the ride. 

Impey is also considering a move away from Alberton despite being contracted until the end of 2018. AFL.com.aureported last week that the Bulldogs and Hawthorn were among the clubs trying to lure the dashing defender to Victoria. 

Trengove told NAB AFL Trade Radio he hoped his long-time friend would remain his teammate at Whitten Oval.

"I'm working on him, boys. He's in a unique situation where he has to make a decision and I can't make it for him," Trengove said of Impey.

"I'd love to make it for him and I know where he'd end up if I was making it but he'll make a decision in the next coming weeks and he'll make the right decision for what's best for him."

AFL.com.au reported on September 1 the Bulldogs were the frontrunners to lure Trengove from Port, having overtaken other interested clubs headed by Carlton.

The 26-year-old Victorian is a restricted free agent so the Power could have matched the Bulldogs' offer. However, they were widely expected not to exercise this right, largely because letting Trengove go creates the salary cap space they need to bring in Tom Rockliff and, most likely, Steven Motlop via free agency. 

Bulldogs list manager Jason McCartney told AFL.com.au on Friday morning the club was confident Trengove would make a instant impact at his new club. 

"He's got great experience, he's a versatile player having played in all three areas of the ground. He also has great leadership and is extremely competitive. He's a 153-game player and you think of the greats that we've had go out of our club this year in Bob Murphy and Matty Boyd, he fits a nice age profile in our group too," McCartney said. 

Trengove, 197cm and 97kg, will help strengthen the Bulldogs' spine, and his ability to play at either end of the ground and pinch-hit in the ruck gives them added flexibility.

"The Doggies appealed to me as a club, I think that I can help out and make an impact there straight away which also excites me," he said. 

"I'm not 100 per cent sure where my best footy will be for the Dogs. I think I'll play in a number of positions at the Doggies like I did at Port. I think I can still be effective as that second ruckman and give the main ruckman a fair chop-out. I think that I'm able to come to ground a lot better than some of the ruckmen because of my size."

The former Calder Cannon appeared likely to re-sign with Port earlier this year, but began to reconsider his future when he was dropped following the Power's humiliating 84-point flogging by Adelaide in round 20.

Trengove was best on ground the next week in the SANFL with 23 possessions and two goals, but was unable to earn a senior recall before the end of the year, watching Port's elimination final loss to West Coast from the stands of Adelaide Oval.

Port's pending acquisition of fellow free agents Rockliff and Motlop means it won't receive a compensation pick for Trengove. 

Recruited with pick No.22 in the 2008 NAB AFL Draft, Trengove played 153 games for Port, including its first 19 this season. He finished seventh in the club's 2016 best and fairest award. 

- with Josh Cheadle and Nat Edwards

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