This Sunday, Harvey will be at the top of Longmire's planning agenda when his Swans take on the Kangaroos at the SCG.
When Harvey arrived at North ahead of the 1996 season, Longmire was sidelined for that entire year with a serious knee injury, but they would play together between 1997-1999.
All these years later, Longmire is into his fourth season as the Swans' senior coach and Harvey is seemingly still at the top of his game.
Averaging 23 possessions in 2014, Harvey has also kicked seven goals through three games and helped the Kangaroos end Port Adelaide's unbeaten start to the year at the weekend.
"I played with 'Boomer' and he's still playing well," Longmire said on Monday.
"He's a really, really top-line player.
"He'll go down in the history of the North Melbourne Football Club as one of the all-time greats.
"He's still playing at an extremely high level and he's still a thorn in opposition teams' side.
"His impact on games is still high and he's not just getting through his career, he's almost getting better and better.
"I don't know what he's eating, but I'll have to get on that diet."
John Longmire celebrates his 1999 premiership win as teammates including a younger Brent Harvey (far left) looks on
The 10th-placed Kangaroos are sitting one win and one spot ahead of the Swans ahead of another early-season crunch game.
Longmire certainly took notice of North's effort to run over the top of Port at Etihad Stadium.
"They had a terrific win considering Port Adelaide were in red-hot form," Longmire said.
"They won all the stats – contested ball, uncontested ball, clearances – they had a great game.
"So they'll be really confident coming up here to the SCG on Sunday that they're in good form as well.
"We expect a really tight contest."
The Swans also ignited their season in round three with a resounding 63-point victory over the Crows in Adelaide, their first win of the year.
They did it without Sam Reid (Achilles) and Craig Bird (calf), who were added to an injury list that includes Kurt Tippett, Adam Goodes and Alex Johnson.
Bird is expected to recover and push for a recall against North, but the news isn't so positive with Reid.
"'Reidy' will be out for a couple more weeks," Longmire said. "His Achilles is still a bit sore.
"He's walking around all right, but he won't train this week and might not have the preparation for next week.
"He might be two weeks away."
On the plus side, the Swans may soon regain the services of Tippett, who hasn't played since injuring his knee in last year's finals series.
The key forward got through an important training session last Friday and, if his knee continues to cope with an increased load, he could be an outside shot at featuring in next week's clash with Fremantle.
"We expect him to train on Wednesday, which is good news," Longmire said.
"He won't be available this week, but we'll see what happens next week, depending on how he pulls up.
"He steps up a notch this week and he's coming along pretty well."
Twitter: @AFL_JD
