How many times have former UFC champs Anthony Pettis and Benson Henderson fought? Everything you need to know about tonight's KC 43 headliner

A rivalry will be renewed tonight as Anthony Pettis and Benson Henderson are set to compete in the main event of KC 43.

KC 43 is expected to be an entertaining night of fights and best of all, it will be completely free for fans to watch as it will air live on Karate Combat's YouTube channel, as well as UFC Fight Pass.

The former UFC and WEC lightweight champions are no strangers to each other as they have competed twice before in MMA, with both bouts being contested for a lightweight championship.

There is a nostalgic element to the KC 43 main event as it takes place almost 13-years to the day of their memorable encounter in the WEC. Pettis and Henderson's first encounter took place at WEC 53, when they fought in the main event for the lightweight championship in the promotion's final event before merging with the UFC.

The WEC bout is remembered for the famous 'Showtime Kick', which saw Anthony Pettis run off the cage wall and drop Henderson with a head kick. It was an entertaining bout that saw 'Showtime' earn a unanimous decision win to become the final WEC lightweight champion.

The highly anticipated rematch took place in the octagon three years later at UFC 164. The rematch saw Anthony Pettis challenge Benson Henderson for the UFC lightweight championship and history repeated itself as he dethroned 'Smooth' in decisive fashion after submitting him via armbar at 4:31 of the first round.

Despite their memorable rivalry, there was no animosity between the former UFC and WEC lightweight champions in either fight. In fact, they have been very friendly ahead of their KC 43 bout and even did media rounds while sitting next to each other, which shows that their rivalry is strictly competition-based and not at all personal.

It will be interesting to see what transpires when Anthony Pettis and Benson Henderson take their rivalry from the cage to the Karate Combat pit tonight and which fighter will have the advantage in that environment and ruleset.