UFC Fight Night 289 predictions: Rosas Jr. vs Barcelos picks

Last Saturday the betting market had Raul Rosas Jr. at -196 to beat Raoni Barcelos. On Tuesday morning he was -184. Now, across 18 sportsbooks, he is -160, and Barcelos has come in from +160 to +133. Somebody spent the week betting on the 39-year-old.

Our model has not followed them. It had Rosas Jr. at 70.6 percent when I wrote about the age gap on Wednesday, and its latest run still has him at 70.6 percent. The market, once you strip out the bookmakers' margin, now gives him 58.9 percent. That is a twelve-point disagreement in a main event, and it has been widening since Tuesday.

UFC Fight Night 289 is at the Meta Apex in Las Vegas tomorrow, Saturday, September 26. Prelims start at 5 p.m. ET (21:00 UTC), the main card at 8 p.m. ET (00:00 UTC Sunday). Here is the whole card, model against market, and then my picks, which do not always agree with either.

The card, model against market

Market percentages below have the bookmaker margin removed, so they add up to 100 for each bout and can be compared straight against the model.

The "earlier" column is the first price once five or more books were posting (a one-book number is not a market), except for the main event, where it is the week's peak. Osmanli vs Akylbek Uulu only has consensus history from Thursday.

Rosas Jr. vs Barcelos: the market blinks

Photo: Chamatkar Sandhu / CC BY 3.0

The path of this line is the most interesting thing on the card. Our consensus history opens on September 17 at -180 with a single book. As more books posted it shortened to its peak of -196 on September 19. It sat between -177 and -187 for three days. Then, starting Tuesday afternoon, it went almost entirely one way: -177 by Tuesday night, -170 in the early hours of Wednesday, -162 by Wednesday night, -160 now. Nothing about the fight changed in our records. It was just a steady, patient drift toward the older man.

I can see the case the money is making. Rosas Jr. (12-1) is No. 12 in the UFC bantamweight rankings and lives on takedowns: 6.10 per fifteen minutes, against 1.34 significant strikes landed per minute. Barcelos (22-5, No. 13) defends 87 percent of takedowns and lands 4.65 significant strikes a minute. Flip it over and it gets worse for the kid: Rosas Jr. defends only 25 percent of the takedowns thrown at him, and Barcelos attempts 2.51 per fifteen. It is the first five-round fight in the UFC for either man, and Barcelos has won five straight, all of the last four on the scorecards, the most recent a split decision over Montel Jackson in April.

The model sees all of that. Of its five biggest inputs on this fight, grappling is the only one leaning toward Barcelos. It is simply outvoted, and the thing outvoting it is the calendar: Rosas Jr. is 21, Barcelos is 39, and age is by a distance the heaviest input behind the 70.6. I went through why that matters, and how rarely the older fighter wins at a gap like this, in the age-gap piece on Wednesday. Nothing that happened to the line since then has touched either birth certificate.

So which of them is wrong? I have argued myself into Barcelos twice this week, both times on the takedown defense, and both times I came back to rounds four and five. Rosas Jr. does not need to win every exchange, he needs to be the fresher man with ten minutes left, and a 39-year-old who needed a split to beat Jackson over fifteen minutes has not shown me he is the fresher man over twenty-five. The market has moved about as far toward Barcelos as the evidence will carry. I am not moving with it.

Prediction: Raul Rosas Jr. by decision

Dumont vs Perez: the widest gap on the main card

Photo: OnlyFans / CC BY 3.0

First, the good news: on Tuesday I complained that Norma Dumont vs Ailin Perez was buried on the prelims. The UFC's latest listing has it as the co-main event. I will take the win and say nothing more about it.

The main event gets the headline, but this is where the model and the market are furthest apart. Our model gives Ailin Perez 76.1 percent. The market has her at 58.3. The line barely moved through the first half of the week, sitting between +104 and +116 on Norma Dumont from the first price on September 17 through Tuesday. Since then it has drifted toward Perez: +119 by early Thursday, +123 this morning, +129 now. So on this fight the market is walking toward the model, just slowly.

The model's reasoning is legible. Perez (13-2, No. 5) has won six straight in the UFC, the last a decision over Macy Chiasson in February, and she takes opponents down 4.90 times per fifteen minutes. Dumont (13-3, No. 4) is coming off a unanimous loss to Joselyne Edwards in April, an opponent Perez beat in 2024, and she takes it down 1.43 times per fifteen. Dumont is the busier striker, 3.85 significant strikes landed per minute to Perez's 2.88, and she is the one of the two who has beaten former champions. But she is 35, Perez is 31, and every one of Dumont's nine UFC wins went to the judges, which is a thin cushion against a wrestler with control time to bank.

Prediction: Ailin Perez by decision

The rest of the main card

Luis Hernandez vs Sedriques Dumas

This bout did not exist until Thursday. Mickey Gall vs Sedriques Dumas was added to the prelims on Monday; on Thursday Luis Hernandez replaced Gall, and the fight landed on the main card. Hernandez (8-0) submitted Hugo Guillon in the second round at Dana White's Contender Series on September 15, so he will fight here eleven days after that. The first consensus price was -194 with four books up. Within ninety minutes it was -227, and it is -236 now.

This is one of the few spots where the market is ahead of the model: 67.3 percent against our 63.2. Dumas (10-5) has a six-inch reach edge, 79 to 73, but his last three fights produced a no contest with Zach Reese in September 2025 and then submission losses to Donte Johnson and Jackson McVey. Hernandez's Contender Series striking numbers are enormous and come from one fight, which is the whole caveat.

Prediction: Luis Hernandez by submission

Mehemmedeli Osmanli vs Ilimbek Akylbek Uulu

Two UFC debuts, and the reverse of the main event: the market is sure, the model is not. The consensus has Osmanli at -294, 71.4 percent, and that price has not moved since Thursday. Our model gives the 22-year-old southpaw from Baku 58.7 percent. It likes his pre-UFC win and finish rates, but two debutants give it very little UFC evidence to work with. Akylbek Uulu, 23 and from Kyrgyzstan, has three ONE Friday Fights bouts in our records: a decision win in 2023, then TKO losses to Khalim Nazruloev and Dzhokhar Eskiev in 2024.

Prediction: Mehemmedeli Osmanli by TKO

Melissa Amaya vs Valesca Machado

One housekeeping note first: the UFC lists Valesca Machado under her ring name, Tina Black. Same fighter, same booking since August. The line has marched against Melissa Amaya all week: +140 on the first single-book price, +178 once five books were up, +189 now. The market has Machado at 66.9 percent. The model has her at 57.8, and the input holding Amaya up is her unbeaten record before the UFC. Machado's only appearance in a UFC-run cage in our records is a decision loss to Piera Rodriguez on the Contender Series in 2021, so neither woman arrives with much octagon evidence. I side with the favorite, with less conviction than the price.

Prediction: Valesca Machado by decision

The prelims, briskly

Brady Hiestand vs Rinya Nakamura. Nakamura (10-1) has drifted from -328 to -386; the model has him at only 59.7 percent, because Hiestand wants a fifteen-minute wrestling fight and Nakamura's one loss was a fifteen-minute decision. Hiestand has not fought since June 2024, though, and that is a long time. Prediction: Rinya Nakamura by decision

Rodolfo Vieira vs Robert Bryczek. The biggest honest move on the card: a pick'em at -110 each way once five books were up, Vieira -164 now, and the model is past the market at 68.0 percent. Vieira (11-5) wins early on the mat or he probably does not win. Prediction: Rodolfo Vieira by submission, round one

Rodolfo Bellato vs Christian Edwards. The model calls it a coin flip at 51.3 percent for Bellato; the market has him at 61.9 and rising. Bellato (13-3-1) stopped Luke Fernandez in the first round in March; Edwards (8-5) lost a split to Modestas Bukauskas in May. Prediction: Rodolfo Bellato by KO/TKO

Elves Brener vs Josiah Harrell. Brener was a slight favorite once five books posted; now Harrell is -129. The model still has Brener at 52.4 percent, mostly because Harrell (11-1) absorbed 10.9 significant strikes a minute while Jacobe Smith knocked him out in his UFC debut in February. Prediction: Elves Brener by decision

Montel Jackson vs Ricky Simon. The only fight where model and market agree to within two points, Jackson at 66.7 and 65.2. Both men's most recent losses came to Barcelos: Simon by unanimous decision in November, Jackson by split in April. Prediction: Montel Jackson by decision

John Castaneda vs Heili Alateng. Castaneda (21-8-1) has gone from -278 to -383; the model is a little less sure at 71.5 percent. Prediction: John Castaneda by decision

Vanessa Demopoulos vs Yazmin Jauregui. An honest correction here. When I wrote about this card on Tuesday, the model had Demopoulos at 34.3 percent. It now has her at 17.9, not far from the market's 13.2. So the model does move, and on this fight it moved a long way. It just has not moved on Rosas Jr. Prediction: Yazmin Jauregui by decision

Where that leaves it

On most of this card the model and the market have spent the week converging, from one side or the other. On the main event they have spent it pulling apart, and the side doing the moving is not the model. By Sunday morning one of them will have been wrong in public about a 21-year-old and a 39-year-old, and I have put my name next to the one that has not blinked.

Model numbers for every bout are on the event page, and you can lock in your own card at the pick'em before the prelims start.