The International Fight Week card is next up for the UFC on pay-per-view. They return to the T-Mobile Arena on July 6 with a two-title-fight main card featuring the best men's and women's fighters in MMA history.

The greatest male fighter ever, Jon Jones, defends his light heavyweight belt against Thiago Santos in the evening's main event, while the greatest female fighter, Amanda Nunes, welcomes Holly Holm into the cage. This is the night of the GOAT.

The main card will also feature a welterweight contender's clash between Jorge Masvidal and Ben Askren, as well as Luke Rockhold's light heavyweight debut.

It's a big fight card to help you celebrate the Fourth of July weekend with a solid undercard filled with action fights to help supplement the title tilts leading the charge.

UFC 239 Full Fight Card

• UFC Light Heavyweight Championship: Jon Jones vs. Thiago Santos
• UFC Bantamweight Championship: Amanda Nunes vs. Holly Holm
• Jorge Masvidal vs. Ben Askren
• Jan Blachowicz vs. Luke Rockhold
• Diego Sanchez vs. Michael Chiesa
• Claudia Gadelha vs. Randa Markos
• Gilbert Melendez vs. Arnold Allen
• Sean O'Malley vs. Marlon Vera
• Alejandro Perez vs. Yadong Song
• Edmen Shahbazyan vs. Jack Marshman
• Julia Avila vs. Melissa Gatto
• Ismail Naurdiev vs. Chance Rencountre

The Main Event: Jon Jones vs. Thiago Santos

For the second-straight light heavyweight title defense, a former middleweight who has found new success in the heavier division will get a crack at Jon Jones for the championship.

Thiago Santos was a solid middleweight who made a name for himself with devastating finishes. He won five of his last six middleweight contests with a lone loss to David Branch in April 2018. Last September, he answered the UFC's call for a light heavyweight bout against Eryk Anders. He won a "knockdown drag 'em out" fight after the referee stopped the bout at the end of the third round.

Feeling rejuvenated by not having to cut as much weight, Santos stuck around at 205 to meet Jimi Manuwa. It was another knockout win and moved him right into the thick of the hunt for a title shot. He returned two months later to fight Jan Blachowicz and took yet another TKO victory.

That was all the UFC needed to see to award him a title shot. 3-0 at light heavyweight, three KO/TKO wins.

Awaiting him is the greatest light heavyweight champion in MMA history and arguably the best fighter to ever do it: Jon "Bones" Jones.

When Jones returned in December to win the vacant light heavyweight belt, he looked as good as ever. In an attempt to stay active, he returned nine weeks later to defend the newly won belt against Anthony Smith. He went the full 25 minutes with Smith but was never in any danger.

To say it's an uphill battle for Santos may be overstating it. Per BestFightOdds, Jones is as high as a -714 favorite (bet $714 to win $100).

While there may not be a reason to suspect Jones will struggle, big upsets have happened before, and Santos has the power to end a fight with one strike at any moment. He will have to throw caution to the wind if he wants to shock the world.

It can be a disappointment Jones doesn't appear to have an equal in the division just yet, but there are only so many times you get the opportunity to witness him in action. This is one of those times.

The Co-Main Event: Amanda Nunes vs. Holly Holm

Amanda Nunes took control of the bantamweight division by destroying Miesha Tate and retiring Ronda Rousey. After two more title defenses, she moved up for the biggest challenge of her career.

And she did the unthinkable. Nunes took the featherweight title off Cris "Cyborg" Santos by knockout in under a minute. It was jaw-dropping and instantly made Nunes the greatest female fighter of all-time. Other fighters ran from Cyborg and avoided the fight. Nunes welcomed it.

She returns to the bantamweight division for another spectacular title defense. Holly Holm will try to regain her title and end Nunes' reign.

Including her title loss, Holm is 2-4 in her last six fights. It's not a good record, but digging deeper shows a much more nuanced story.

After dropping her title to Tate, Holm saw mixed results. She lost a close bout to Valentina Shevchenko and had a contentious decision loss to Germaine de Randamie for the inaugural featherweight title. After knocking Bethe Correia out, Holm challenged Cyborg. She put up a quality effort but came up short. She returned last June with a decision win over Megan Anderson.

Holm will provide the most challenging matchup for Nunes. On the feet, Holm can establish range and slow the fight down. Against Cyborg, Holm showed her strength in the clinch. Nunes will be forced to be the best version of herself if she wants to have another successful defense.

Fight fans may not see the wild swinging they saw in the Cyborg vs. Nunes bout. Instead, they are likely to see tactics come into play from both sides. Watching their mid-round adjustments will be the difference in who wins and loses.

This is the best women's fight available regardless of weight and is the true main event of UFC 239.

Fight to Keep an Eye On: Jan Blackowicz vs. Luke Rockhold

Anthony Smith moved up and got a title shot. Thiago Santos moved up and will get his title shot on this  same card. So, why not Luke Rockhold?

Rockhold has already won gold at middleweight, and it came when he was deleting his body to make the division. Rockhold was one of the biggest middleweights. At light heavyweight, we may see the best version of Luke Rockhold.

And there is heat between him and Jones. Rockhold has continually prodded at Jones. This included a callout as recent as January via TMZ Sports.

Standing in his way will be Jan Blachowicz.

Blachowicz stumbled out of the gate in his UFC career, but he got things moving in the right direction in 2017. After a four-fight win streak, he dropped a fight in February against Thiago Santos. He knows he is close to being a legitimate title contender, and beating Rockhold would allow him to regain his position among the top contenders.

It is a much more important bout for Blachowicz. He can get back in the win column, move back into title contention and, most importantly, grab a win over a notable name to get recognition among the fans. If Rockhold loses, he was just a middleweight who couldn't make it at a higher weight class. He has a built-in excuse that fans will buy. He can always return to 185.

Blachowicz cannot.

The stakes of this fight with two fighters wanting to make a title run will make them more aggressive leading to a more action-packed fight. It's a sleeper in regards to action and a fight with a lot of importance to the 205-pound belt.

Best of the Rest

Jorge Masvidal vs. Ben Askren

Ben Askren had a fun UFC debut. He got dumped on his head, survived and still ended up with a submission win. On the other side of the cage, Jorge Masvidal has worked his way into the title hunt after a stunning KO over Darren Till. Can he stop Askren's wrestling to stun the division again?

This is an intriguing matchup inside the cage, but their personalities outside of the Octagon are perhaps even better. It is possible this could even be a title eliminator. There is a lot to like about the matchmaking here, and you cannot go wrong with two of the best welterweights competing on a PPV undercard.

Diego Sanchez vs. Michael Chiesa

There isn't much significance to this fight as it pertains to the title, but it's worth your attention as a possible Fight of the Night contender. These two are guaranteed fun. This is a popcorn fight. Make sure you have your snacks ready.

Sean O'Malley vs. Marlon Vera

This is another Fight of the Night contender, but it's worthy of your attention for O'Malley's return to the cage. He is an undefeated prospect who was making waves in early 2018. Over a year since his last bout, fans will get to see how much he has grown as a fighter. Circle O'Malley on the bout sheet as the fighter who can grab more new fans at UFC 239.

Claudia Gadelha vs. Randa Markos

The top of the strawweight division seems set for the remainder of 2019. Tatiana Suarez and Rose Namajunas are the next title contenders without any competition behind them. The winner of Claudia Gadelha vs. Randa Markos will move right behind those two and set themselves up for a possible run at the title in 2020.

Gadelha has previously been at the top. She came up just short. In the past year, she has fallen back into the pack. It'll be over six months since her loss to Nina Ansaroff, and coming back against Markos will help to determine if she is past her prime or revitalized as a top threat. For Markos, it's a chance to get her biggest win to date.

This fight will tell us a lot about each woman's future in the division and help shape what is to come in 2020.