Earlier this month, Israel Adesanya and Dustin Poirier became the sixteenth and seventeenth interim champions, respectively, in UFC history.

A unification fight between Poirier and Khabib Nurmagomedov has already been rumored for Abu Dhabi in September, whilst Robert Whittaker has also suggested a September date, in Sydney, for his unification bout with Adesanya.

This means that before the year is out, we could see the ninth and tenth title-unification bouts in UFC history. Perhaps somewhat surprisingly, it is the interim champion who historically gets the better of these contests.

Whether this is simply coincidence, or a reflection of the hunger of an interim champion, in the 8 unification bouts in UFC history thus far, interim champions lead undisputed champions by 5 wins to 3.

Only two men; Brock Lesnar and Georges St-Pierre, have ever managed to defeat an interim champion in a UFC title-unification bout. The table below breaks down each unification fight (interim champion vs. undisputed champion) in UFC history.

It’s also worth noting that since Randy Couture’s dominant five-round unanimous decision victory over Tito Ortiz back in 2003, every interim champion who came out victorious in a unification fight won their contest inside the distance.

Although winning an interim championship usually means your next fight is against the undisputed champion, there have been some exceptions to that rule, most notably Tony Ferguson, who was stripped of his interim championship after just six months and one fight withdrawal.

Dana White explained at the time that Ferguson’s title would ‘go away’ as the undisputed title fight (Khabib Nurmagomedov vs. Al Iaquinta) was going ahead without him. However, on the two previous occasions in UFC history where an undisputed title fight excluded the reigning interim champion; Randy Couture (c) vs. Brock Lesnar and Michael Bisping (c) vs. Georges St-Pierre, the respective reigning interim champions Antônio Rodrigo Nogueira and Robert Whittaker both kept their belts.

As the graph above shows, there have never been more than two interim champions reigning concurrently in UFC history. If the UFC were to introduce another interim championship before Poirier or Adesanya either unified or lost their interim titles, it would be the first time in promotional history that three interim champions reigned simultaneously.

Despite the recent criticism the UFC has received for crowning interim champions too frequently, Poirier and Adesanya picking up their belts brought to an end the longest spell (10 months) that the UFC has gone without crowning an interim champion since going from July 2012 until November 2014 without introducing such a title.

That said, there’s no denying the UFC’s recent propensity for introducing interim championships, having crowned 7 interim champions across the first 21 years of the promotion’s existence, then 10 interim champions in the following 5 years.

Although Poirier and Adesanya will need more than simply past precedent to defeat two champions whose current winning streaks both appear in the all-time top-ten list of consecutive UFC victories (11 for Khabib and 9 for Whittaker), perhaps we shouldn’t be so quick to consider the status of an interim champion too far off that of their undisputed counterpart.