Last night Brock Lesnar announced his retirement after losing his second fight in a row, leaving the UFC without it’s biggest pay-per-view star as they head into arguably their most important year yet in 2012 as they officially hit the mainstream with their new television deal on FOX.

The former heavyweight champion is the only fighter in the history of the UFC who’s been consistently able to draw over 1 million PPV buys, and it may be quite some time before they find someone who can adequately replace him.

In many ways Lesnar was the perfect storm as far as an MMA superstar goes – a heavyweight with an almost unparalleled physique and athleticism, legitimate wrestling credentials, a larger than life personality and significantly an avid fan-base from his pro-wrestling days which undoubtedly helped his bankability.

When that all translated into a successful fighter inside the Octagon the UFC capitalized big-time, pushing their pay-per-view sales to new heights.

With Lesnar now out of the picture that level of success will be hard to replicate. You only have to look at the rest of the UFC’s roster to see how difficult it is to produce genuine superstars like Lesnar.

As things stand only Georges St.Pierre currently enjoys anything like Lesnar’s drawing power, generally garnering around 700 – 800,000 buys for his fights.

Beyond that the numbers slide off dramatically. Even a young superstar in the making like light-heavyweight champion Jon Jones with the right look, next-level skills and a string of high profile wins in the Octagon hasn’t yet been able to reach anything close to those heights yet, averaging around 400 – 500,000 PPV buys in 2011.

With Lesnar gone, GSP expected to be out injured for most of 2012 and Jones planning on a six month hiatus from the sport after a busy 2011 it’s hard to see how the UFC are going to make up the numbers financially next year, even when you factor in their new FOX deal.

Some will argue thatAlistair Overeem is someone who they can look to build upon and he’s certainly now as marketable a fighter as they have in the division.

However, though he’s as impressive a physicial specimen as Lesnar, is comfortable on the mike and is a wrecking machine in the cage he doesn’t yet enjoy the same level of star power that the former pro-wrestler commanded or the awareness amongst the casual fanbase.

In order to event get close to that level he’s going to have to go on a tear through the top fighters in the division, and with Junior Dos Santos, Cain Velasquez and Frank Mir amongst those queueing up to fight him that will be no easy task.

So, make no mistake, though they may deny it publicly Lesnar’s loss was a huge blow for the UFC at a pivotal moment in their history.

Don’t get me wrong, it’s not the end of the world – the UFC will continue to grow, new stars will emerge and the FOX Deal will accelerate that, but who knows how long it will be before they unearth another ‘lightning-in-a-bottle’ star like Brock Lesnar.