"They've been the best Broncos side since 2006 - you would have to say they are the best Broncos side in a fair while," said Bellamy, who served under Bennett at the Broncos before taking the Melbourne reins in 2003.
"They led this year for most of the journey and that is not easy in this competition.
"They've been ultra consistent all year.
"They are in a prime spot to go all the way."
Brisbane made Bellamy sit up and take notice when they broke an eight game losing streak against the Storm 14-12 in round 15 at AAMI Park.
Melbourne have won 19 of their last 22 clashes with Brisbane.
The Broncos have not defeated the Storm at Suncorp Stadium since 2009.
But Melbourne have taken the Broncos threat so seriously they set up an Origin-style camp on the Sunshine Coast to prepare for Thursday night's match.
"There's a rivalry but it's based on respect," Storm playmaker Cooper Cronk said of Brisbane.
"We are looking for a bit of consistency ahead of the finals.
"We have lost to teams below us on the ladder and played some really good footy against teams above us.
"We know our best is super competitive and our average games are below par, not to the standard we want to play at.
"We have to address that."
Melbourne can keep their top four hopes alive with a win but must rely on other results to go their way.
"We are well aware of the circumstances," Cronk said.
"Destiny is still in our hands in some regards."
-AAP