UFC Betting Explained: Which Events Have More Upsets

Here's a pattern most UFC bettors never notice: they bet the same way on every card. They parlay three favorites on a Fight Night prelim card and wonder why two of them got knocked out by unknowns. Or they fade a PPV main event favorite because "upsets happen" and watch that favorite cruise to a decision.

Different UFC events produce different upset rates. And if you're not adjusting for this, you're leaving money on the table.

This guide breaks down exactly which events produce more upsets and how to adjust your betting accordingly.

Read more: The Complete Guide to UFC Fight Night vs PPV Betting

Overall Favorite vs Underdog Baseline

Before we slice by event type, let's establish the baseline. What's the normal upset rate in UFC?

Long-run UFC data shows favorites win a clear majority of the time, with underdogs cashing just under a third of fights.

In a 709-fight sample:

• Favorites won 68.12% of bouts (483 wins)
• Underdogs won 31.88% (226 wins)

This is the baseline: roughly 2 of 3 favorites win, 1 of 3 underdogs. Before we slice by platform or card position.

Keep this in mind. When someone says "upsets happen all the time in UFC," they're wrong. Favorites win more than twice as often as underdogs overall.

But that average masks important differences across event types.

Which Event Segments See More Upsets?

A detailed platform study broke fights into PPV, main card, and FB/FP (Facebook/Fight Pass) prelims. The results show clear patterns.

FB/FP Prelims (Early Prelims)

Upsets occur 0.78% more often than on other platforms and 1.25% more often than the all-fight average.

This aligns with intuition: early bouts feature less established fighters and are harder to price accurately.

Why early prelims produce more upsets:

• Fighters with 0-2 UFC fights (unknowns)
• Debutants vs debutants (both unknowns)
• Less tape and data available
• Books struggle to price accurately
• Public has no idea who these people are

PPV Fights

Underdogs pull off fewer upsets in raw percentage terms. Favorites win at their highest rate here.

Books and bettors have better reads on big-name fighters with long resumes.

Why PPV favorites are more reliable:

• Established fighters with 8+ UFC fights
• Extensive media coverage and analysis
• More data for books to price accurately
• Sharper markets with higher liquidity

Main Cards Overall

When you adjust for odds (implied probability), underdogs actually overperform their prices most on main cards, while favorites overperform expectations the most on FB/FP prelims.

This seems contradictory but makes sense: on early prelims, even the favorites are unknowns, so they outperform weak pricing. On main cards, the underdogs are quality fighters who get underestimated.

The author stresses that variance in these numbers is small (just a couple of percentage points) but they do confirm what sharp bettors already assume: more chaos on low-profile prelims, more stability (but also sharper pricing) on PPVs.

Free Cards vs PPVs: Where Do Upset Profits Cluster?

Action Network looked at every UFC event in 2021 and asked: "What if you just bet favorites on PPVs and underdogs on free ESPN/Fight Night cards?"

The results are striking.

Free Cards (ESPN/Fight Nights)

Blindly betting every underdog at 1 unit each would be up about 2.5 units on the year (roughly 0.14 units per event).

ROI came out just over 1%, assuming roughly 12 fights per card.

What this means: There's systematic underdog value on Fight Nights, even without any analysis. Just betting every dog blindly made money.

PPV Cards

Blindly betting every favorite at 1 unit each would be up about 4 units (roughly 0.2-0.3 units per event, about 3% ROI).

What this means: PPV favorites are underpriced relative to their actual win rate. Blindly backing them was profitable.

Interpretation

Upsets (and profitable dogs) appeared more frequently on free cards, reflecting the higher uncertainty around prospects and debutants.

Favorites held serve (and were modestly profitable relative to juice) on PPV cards, where fighter quality and data depth are greater.

The working theory: PPVs host more established fighters with longer resumes (books and market price them better), while free cards have more unknowns, making it easier for underdogs to be mispriced and pull upsets.

Important caveat: This doesn't mean bet every underdog on Fight Nights and every favorite on PPVs. It means the baseline value leans that direction. You still need analysis.

Biggest Upset Events & Outlier Cards

Some individual UFC events are notorious for extreme upset runs. These are the outliers that make betting UFC so volatile.

UFC Fight Night: Mir vs Bigfoot (2015)

Cited as "the biggest upset event in MMA history."

Of 11 fights, 10 underdogs won. A nearly unheard-of upset rate on a single card.

If you parlayed three favorites on that card (which most bettors did), you went 0-3. If you bet a few underdogs, you probably had your best night ever.

2023 Example

Alexa Grasso submitted Valentina Shevchenko at roughly +600 vs -900, the largest betting upset of that UFC year.

This was a title fight on a PPV. Even PPVs can produce massive upsets, just less frequently than Fight Nights.

These outliers illustrate how Fight Nights and certain non-PPV cards can produce extreme sequences of underdog wins that heavily skew short-term data.

One crazy upset card doesn't mean the trend is broken. It means variance exists. But over time, the patterns hold.

Why Some Spots Produce More Upsets

Several structural factors explain why upsets cluster in particular event types and card slots.

Less Information on Prelims and Free Cards

Early-card and ESPN bouts feature debutants and low-sample fighters, making it harder to evaluate true skill and competition level.

Books and the public misjudge more often when there's no data.

Example:

Brazilian prospect making UFC debut on a Fight Night early prelim. He's 12-0 in regional MMA but you can't find good footage. The book opens him at +180 vs a 3-3 UFC veteran.

Is the prospect good or just untested? Nobody knows. That uncertainty creates mispricing.

More Debut vs Debut or Low-Experience Fights

When both fighters are new to the UFC, model priors are weak. Action Network notes this scenario rarely happens on PPVs but is more common on free cards.

When both fighters are unknowns, even the favorite is a guess. Upsets are more likely because neither fighter has a proven edge.

Sharper, More Liquid PPV Markets

Higher limits and more money hammer PPV lines into shape, especially on main card fights, reducing mispricing and upset frequency relative to implied probability.

How this works:

PPV main event opens at Champion -250 vs Challenger +200. Within hours, sharp money has analyzed every angle and bet accordingly. The line settles at a more accurate -220 / +180.

Fight Night early prelim opens at Fighter A -150 vs Fighter B +130. Less money flows, less analysis happens, the line stays -150 / +130 even if it's wrong.

Public Bias and Narrative

On PPVs, heavy public money on stars can temporarily distort prices, but over a card the extra liquidity still tends to push odds close to true win rates.

On quieter Fight Nights, smaller but sharper action can move lines more, and errors linger longer on prelims.

Shurzy Tips: How To Use Upset Patterns

Here's how to actually apply this knowledge to your betting strategy.

Expect More Live Underdogs On

Free ESPN/Fight Night cards in general: The data shows systematic underdog value here. Don't shy away from dogs when your analysis supports them.

FB/FP / early prelims: Favorites historically get upset slightly more often here. Be skeptical of heavy favorites in unknown matchups.

Debut fights: When one or both fighters are making their UFC debut, the upset probability is higher than the line suggests.

Expect Favorites to Be More Reliable On

PPV main cards and featured fights with established names. These fighters perform closer to their implied probability.

Main events generally: Both PPV and Fight Night main events feature better fighters who are less likely to have hidden flaws.

Established champions: Longstanding titleholders rarely get upset (though it happens). The market prices them accurately.

Actionable Adjustments

On Fight Nights and early prelims:

Be open to underdog shots when your tape and numbers support them. The environment is structurally friendlier to upsets and mispricing.

Don't overstack parlay favorites on these slates. They bust more often than their PPV equivalents.

Use smaller units on favorites. The upset rate is higher, so protect your bankroll.

On PPV cards:

Treat strong favorites with more respect. Data suggests they underperform less often relative to price.

Look for selective underdogs on main cards where your model says odds significantly underrate their true chances, but don't expect wild dog runs every PPV.

Moderate favorites (-150 to -300) with clear paths to victory are often good value.

Across all events:

Use upset patterns as context, not a system. The long-term differences are measured in a few percentage points, so matchup and price still matter far more than card label.

Track your own results by event type. You might crush Fight Night underdogs but struggle with PPV favorites. Know your strengths.

Parlay Strategy Adjustments

Fight Night parlays: Use fewer legs (2-3 max) and expect higher failure rates. The upset potential is real.

PPV parlays: You can extend to 3-4 legs with more confidence, but still keep stakes small.

Early prelim parlays: Avoid entirely. Too much chaos. Stick to singles.

Bottom Line

Upsets are slightly more common and often more mispriced on free cards and early prelims, while PPVs (especially main cards) are where favorites hold strongest and pricing is tightest. The differences are small but consistent. Over hundreds of bets, these patterns compound into real edge. Adjust your strategy accordingly and you'll capture value that other bettors miss.

Read more: The Complete Guide to UFC Betting for Beginners

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