Bontempelli, who was due to be off contract at the end of next season, has penned a two-year contract extension to stay at Whitten Oval at least until the end of the 2021 season.

The length of tenure makes the premiership star eligible for free agency at the end of his contract but Bontempelli said there were other factors at play in determining his new deal.

"You've got to consider those things with football now (but) it wasn't a huge part of it," he said.

"I can understand the speculation around a long term deal ... it suits particular players and particular clubs.

"We were happy to extend for two. Most of all it keeps me accountable to want to grow more and be the best player I can be.

"It's been home to me for so many years now that I don't see myself going anywhere else.

"There's not too much more to it than that."

The 22-year-old star declined to confirm reports his new deal pushed him into an elite bracket of AFL players earning a seven-figure wage.

Bontempelli is back in pre-season training after spending a fortnight on the US west coast, training at the Nike headquarters in Portland and UCSD in southern California.

He said that was part of "freshening up" his training regime in search of improvement.

He is one of just four Bulldogs players to have won multiple club championships and a flag - the others being club icon Ted Whitten, forward Jack Collins from the class of 1954, and the recently retired Matthew Boyd.

Bontempelli was denied a third best and fairest in this year's count, coming third in a 19-game season behind Lachie Hunter.

The Bulldogs were never seriously in the finals race in 2018 after losing four of their opening five fixtures, eventually finishing 13th with eight wins.

Already a much-changed side from their 2016 triumph, coach Luke Beveridge went again in this year's trade period.

Taylor Duryea and Sam Lloyd have arrived with Luke Dahlhaus, Jordan Roughead and Marcus Adams departing.

Bontempelli said the emergence of fresh talent like Hunter gave him confidence in the Bulldogs' rebuild.

"We have a really talented group of young players and I'm excited about what they are capable of producing with a bit more experience under their belts," he said.

Australian Associated Press