Bad blood between Conor McGregor and Floyd Mayweather has been brewing for over two years. On Aug. 26 the pair will finally get to settle their differences. So how did an MMA fighter and a boxer grow to hate each other so much?

July 2015: Conor McGregor appears on Conan O’Brien.

This is the official start of the beef. McGregor appeared shortly following Mayweather’s fight with Manny Pacquiao and famously said:

“If you’re asking whether I’d like to fight Floyd, I mean — who would not like to dance around the ring for $180 million.”

July 2015: Mayweather’s uncle responds to McGregor’s comments.

Jeff Mayweather hit back following Conor’s late-night appearance, saying that the UFC superstar “wouldn’t last 30 seconds” in the ring with Floyd, and saying his nephew could beat McGregor “with one hand.”

Dec. 2015 Floyd Mayweather speaks.

The first recorded instance of Mayweather engaging McGregor came in an interview with Fight Hype. Mayweather said that the different perception of the two fighters was due to race, despite their approaches being similar.

“They say he talk a lot of trash and people praise him for it, but when I did it, they say I’m cocky and arrogant. I’m telling you racism still exists.”

Jan. 2016: Conor McGregor takes this personally.

On his Instagram account, McGregor fired back — but importantly was the first time he openly challenged Mayweather.

“Floyd Mayweather, don't ever bring race into my success again. I am an Irishman. My people have been oppressed our entire existence. And still very much are. I understand the feeling of prejudice. It is a feeling that is deep in my blood. In my family's long history of warfare there was a time where just having the name 'McGregor' was punishable by death. Do not ever put me in a bracket like this again. If you want we can organise a fight no problem. I will give you a fair 80/20 split purse in my favour seen as your last fight bombed at every area of revenue.”

May 2016: Mayweather stokes the flames.

In the months following McGregor’s Instagram post there are more and more rumors that arrangements are being made for the two to fight. Finally Mayweather reveals that he was the source, leaking information about a possible fight.

May 2016: McGregor appears on ESPN’s Sunday Conversation.

During an interview McGregor says that Floyd’s rumors aren’t true. He continued to say that there were rumors that Mayweather would make $100 million from a potential fight, while he would only make $7 million. He says that “He needs me, more than I need him.”

This is where things get silly.

Both Mayweather and McGregor post fake flyers for the fight, which puts gas on the fire. From here the two jab back-and-forth over the possibility of the fight, with the impasse routinely being how much money they would both be paid.

McGregor kept contending that he deserved more money than the fight as offering, while Mayweather poked fun at Conor’s net worth — saying he didn’t deserve being paid more than $2.5 million.

Nov. 2016: Things progress.

Conor McGregor is issued a boxing license in the state of Nevada, which re-ignites rumors that the fight may actually be happening.

Jan. 2017: McGregor makes things personal.

Mayweather’s history with C.J. Watson is well documented, and you can find the details here.

Feb. 2017: A new back-and-forth.

Floyd tells fans he’s happily retired and will not return to the ring. McGregor claps back with a photo of him arriving in Las Vegas boasting that “Floyd has retired on my arrival.”

This prompts Mayweather to tell McGregor that he’s ready to fight, and to talk to the UFC to make it happen.

Mar. 2017: Mayweather announces that he is un-retiring to beat Conor McGregor.

“No more excuses about the money, about the UFC, sign the paper with the UFC so you can fight me in June.”

May 2017: The fight is on.

Both fighters sign their contracts and begin their three-month media tour, which takes the fight to this point. There have been more personal attacks, more bad blood, and here we are. After two years the fight is going to happen.