On Top regularly featured the likes of current UFC star Nico Musoke and the respected, not to mention highly entertaining, Lithuanian Sergej Grecicho.
Meanwhile, rivals Vision showcased Robert Whiteford's demolition of the world's biggest featherweight - giant Swede Martin Svensson.
Whiteford has since gone on to become the first Scot to fight in the UFC, while On Top alumni Joanne Calderwood is set to become the second, thanks to a stint on an upcoming series of The Ultimate Fighter.
But around the time both promotions were flying high, it suddenly went quiet.
Scotland went from having one of the healthiest MMA scenes outside America to just another nation trying to grow the sport from the ground up.
Seemingly overnight, our two marquee promotions disappeared.
Vision, with its roots in Sweden, folded and On Top were denied a licence for the planned On Top 7 - a decision taken by Glasgow City Council on the advice of the police.
Thankfully, smaller promotions such as FFC, Art of Combat, Headhunters FC and Caledonian Combat continued their excellent work in the amateur ranks, almost all of them adopting the new Unified Amateur Rules and putting on incredible fights.
Eventually, SFC (Scottish Fight Challenge) rose from the ashes of Vision and went back to its roots in Stirling after being amalgamated into the Swedish Vision brand a few years earlier.
With the SFC back to its brilliant, although admittedly more modest, beginnings, the time was right for On Top to make a comeback.
And on Saturday (March 1) at the Hilton Hotel in Glasgow, the long-awaited On Top 7 will take place.
In the almost 18 months since On Top 6, a lot has happened in Scottish MMA.
Whiteford and Calderwood have made it to the promised land, our most high profile fighter Paul McVeigh has retired and Steven Ray has won, then lost, a CageWarriors lightweight title.
The man behind On Top, Tam Collins, has also made changes.
What was once Scotland's only all-pro MMA promotion will for the first time include amateur bouts on its undercard.
And the desire to hold shows in arenas the size of the Kelvin Hall has also been sidelined, with the more intimate Hilton hosting On Top 7.
Neither of these changes will be seen as a negative by Scottish MMA fans, who have mourned the loss of On Top.
And certainly not when the amateur bouts include a mouthwatering clash between Peter McCafferty and fearless scrapper Mark Duncan, as well as a women's lightweight encounter between debutantes Cris Theodoli and Charlotte Park.
Rising star Chi Chi Ngosa is also on the undercard, while his Dinky Ninja team mate Scot Mulgrew makes his pro debut against Jamie Jones later on.
The main event sees lightweight champ Martin Delaney defend his belt against Gaetan Hurtel, while On Top poster boy Alan 'AJ' Johnston - whose spectacular knockout of Jessin Ayari at On Top 5 has been viewed 95,000 times on YouTube - takes on Josh Collins for the welterweight strap, vacated by Nico Musoke following his call-up to the UFC.
The pro debut of Craig McIntosh, who takes on Matti Laurenson, is another fight to watch out for.
SFC and On Top back in business can only be a good thing for Scottish MMA.
Here's hoping some of the stars in action on Saturday follow in the footsteps of Whiteford and Musoke and are one day gracing the UFC's famous octagon.
ON TOP 7
Champion Martin Delaney vs Gaetan Hurtel for the lightweight (155lb) title
Alan Johnston vs Josh Collins for the vacant welterweight (170lb) title
Iain Feenan v Rafal Lassota at welterweight (170lbs)
Scot Mulgrew v Jamie Jones at 160lbs catchweight
Matti Laurenson v Craig McIntosh at featherweight (145lbs)
Rob Carlin v Craig Derbyshire at 121lbs catchweight
Charlotte Park v Cristiana Theodoli at lightweight (155lbs)
Chilekwa Ngosa v Andrew Wilkie at featherweight (145lbs)
Stewart Graham v John Ross at middleweight (185lbs)
Peter McCafferty v Mark Duncan at bantamweight (135lbs)