UFC 331 lands at Crypto.com Arena in Los Angeles on September 19 with two fights that ask bettors to separate name recognition from price. Joshua Van defends the flyweight title against Alexandre Pantoja in a rematch, while Arman Tsarukyan meets Mauricio Ruffy in a five-round lightweight co-main event. The smart approach is not to pick the fighter you expect to win. It is to decide whether the number gives that fighter a better chance than the sportsbook is charging for.

Van-Pantoja 2 is close on the board, which is exactly where the moneyline deserves the most attention. Tsarukyan-Ruffy is different: Tsarukyan is a large favorite, and bettors have to ask whether laying a steep price is worth it when MMA can turn on one scramble, one clean counter, or one bad minute against the fence. The card is subject to late changes, as always with MMA. Odds move, too. Any number should be checked again before a wager is placed.

Joshua Van vs. Alexandre Pantoja

Van took the flyweight belt from Pantoja at UFC 323 in December, but the 26-second ending did not offer much tape for bettors to treat as a complete answer. Pantoja injured his arm after Van caught a kick and forced him down, ending the title fight before either man could settle into a usual rhythm. That result explains why this rematch has opened tighter than a standard champion-versus-former-champion matchup.

The early market made Pantoja a slight favorite at -120, with Van at +100. Fight-week pricing has shifted toward Van. One current set of odds listed Van at 8/11 and Pantoja at 11/10, while other market reports put Van near -120 with Pantoja around even money or just below it.

Van enters as the younger, faster-volume champion with a 17-2 record. He followed the Pantoja win by stopping Tatsuro Taira in the fifth round at UFC 328, giving him a full championship-round performance bettors can use when considering totals and late-fight props. His recent win over Brandon Royval was a three-round striking war in which the pair landed 419 significant strikes, a UFC record for a three-round flyweight contest. That output does not guarantee another high-tempo fight, but it supports the case that Van can keep working in a long contest.

Sportsbooks build a margin into both sides of a market, known as vig or juice, so the listed implied probabilities usually add up to more than 100 percent. That is why bettors should calculate their own estimate before deciding whether a price is playable.

Pantoja, 30-6, has the resume that pulls casual money. He was a four-time defending UFC flyweight champion before the injury loss and owns the division records for UFC wins, finishes and submission victories. He has 12 career submission wins, carries a three-inch reach edge over Van, and has spent more time in five-round fights than the champion. Those are valid reasons to give him a path to winning, especially if he can turn the rematch into a clinch-and-grappling fight rather than a clean striking exchange.

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Still, bettors should be careful with the idea that Pantoja is automatically “due” to regain the belt because the first fight ended strangely. A void of evidence is not evidence for either side. The first bout did not prove Van is a bad matchup for Pantoja. It also did not prove Pantoja cannot deal with Van’s pace.

LAS VEGAS, NEVADA – DECEMBER 06: Alexandre Pantoja of Brazil reacts to his injury in the UFC flyweight championship fight during the UFC 323 event at T-Mobile Arena on December 06, 2025 in Las Vegas, Nevada. (Photo by Chris Unger/Zuffa LLC)

For a straight bet, Van is more appealing if a book still offers -120 or better. At -135 or shorter, the better choice may be to pass, wait for a Pantoja price that reflects a real payout, or build a prop around a more specific fight script. Pantoja by submission makes sense only if the payout properly compensates for his need to create sustained grappling exchanges. Van by decision or a late finish could fit the champion’s pace, but bettors should compare those prices across books before committing.

Arman Tsarukyan vs. Mauricio Ruffy

Tsarukyan opened around -350 to -380 against Ruffy, while Ruffy opened near +280. By fight week, Tsarukyan had moved closer to -325, with Ruffy around +265 at some sportsbooks. The movement tells a useful story: money has come in on the underdog or the favorite has simply been priced too high for bettors to keep laying it. It does not prove Ruffy will win.

Tsarukyan‘s public profile is easy to understand. He is a leading lightweight contender, an elite wrestler, physically strong in clinches, and built for the pressure game that can shut down a striker’s room to operate. The five-round format also favors a fighter who can bank rounds with takedowns, rides, transitions and top control.

PHILADELPHIA, PENNSYLVANIA – AUGUST 14: Arman Tsarukyan of Georgia is interviewed backstage prior to the UFC 331 press conference at Xfinity Mobile Arena on August 14, 2026 in Philadelphia, Pennsylvania. (Photo by Chris Unger/Zuffa LLC)

Ruffy’s upside is less complicated: he can change a fight with striking. He is coming off a knockout win over Michael Chandler and had previously stopped Bobby Green, two results that have increased his visibility and made him an attractive underdog ticket. But public enthusiasm can go too far when a fighter has highlight finishes. Ruffy’s knockout potential is real; it does not erase the level of wrestler waiting across from him.

Tsarukyan’s move from an opening range around -350 toward -325 does not tell bettors exactly who bet Ruffy or why. A line can move because of respected action, public money, sportsbook liability, or one operator reacting to competitors. The useful takeaway is simpler: anyone who wanted Tsarukyan at a cheaper price may have received a better entry later, while Ruffy backers who took +280 early hold a better ticket than those accepting a smaller return closer to fight night.

SYDNEY, AUSTRALIA – FEBRUARY 01: (R-L) Mauricio Ruffy of Brazil kicks Rafael Fiziev of Kazakstan in a lightweight fight during the UFC 325 event at Qudos Bank Arena on February 01, 2026 in Sydney, Australia. (Photo by Jeff Bottari/Zuffa LLC)

That is why a full Tsarukyan moneyline at -325 can be a tough buy. The favorite may well win. Yet the price leaves little room for a competitive first round, an early knockdown, or a Ruffy finish. A bettor who sees Tsarukyan’s wrestling as the deciding edge could look at Tsarukyan by decision, submission, or a round-and-method prop, then compare those prices against the moneyline. If the method prices are inflated, the moneyline may still be the cleaner option. If they are too short, it is a sign the sportsbook has already priced in the expected grappling script.

UFC 331 Price Shopping Is the Play

The biggest edge on these two fights may not come from predicting a submission or a knockout. It may come from refusing the first price on the screen. For Van-Pantoja, one sportsbook offering Van -120 while another lists -135 is a meaningful difference. On a $120 bet, -120 returns $100 in profit; -135 returns about $88.89. Same fighter. Same fight. Less return.

For Tsarukyan-Ruffy, compare both sides. Taking Ruffy at +280 instead of +240 adds $40 in profit per $100 wager if he wins. Taking Tsarukyan at -325 rather than -380 lowers the amount risked to win $100 by $55. Those are not cosmetic changes. Over a season, they decide whether close bets become costly.

Public bettors tend to gravitate toward fighters they recognize, champions, wrestlers who look “safe,” and knockout artists fresh off viral finishes. UFC 331 has all four ingredients. Van has a belt. Pantoja has the established champion’s resume. Tsarukyan has the contender reputation and a style many fans trust. Ruffy has the highlights.

That makes discipline the whole game. Set your fair price before opening an app. If Van is your 58% pick, -120 is playable and -150 is not. If you make Tsarukyan a 72% favorite, -325 is a pass even if you predict he gets his hand raised. And if the right number never appears, no bet is still a decision.