Conor McGregor’s Biggest UFC Wins That Defined His Career

Conor McGregor is one of the most dynamic and divisive fighters in mixed martial arts. Famed for his biting tongue, brash confidence, and one-punch knockout power, McGregor is a megastar both in and out of the octagon. Ireland’s favorite son has delivered some of the most memorable moments in UFC history, shaping not only his own career but also the sport itself.

This article walks you through four of McGregor’s biggest and most defining wins in the UFC—fights that highlight his skill, work ethic, and ability to thrive under immense pressure.

The Road to Glory

Before diving into the marquee victories, it’s important to remember where it all began. Conor McGregor was born in Dublin to a working-class family. From a plumbing apprentice to a two-division champion, McGregor’s story is one of tenacity, charisma, and, above all, fight-ending power.

Now, let’s explore the wins that made the world take notice of “The Notorious.”

1. Conor McGregor vs. Diego Brandão (UFC Fight Night: McGregor vs. Brandão)

The Fight That Proved His Homecoming Was Golden

By 2014, McGregor had already begun to generate buzz in the UFC. But when the promotion rolled into Dublin, he had the chance to showcase his skills in front of a roaring Irish crowd. Paired with the tough Brazilian brawler Diego Brandão, McGregor was ready to shine.

He wasted no time, putting on one of the most dominant performances of his early UFC career. Throwing bombs with deadly precision, McGregor dismantled Brandão, earning a first-round TKO.

Key Moment: The Dublin crowd erupted as McGregor repeatedly landed his powerful left hand, finally dropping Brandão before the referee stepped in.

Why It Matters: This victory elevated McGregor from a rising prospect to a true star. It wasn’t just a fight—it was a spectacle, proving he could captivate and conquer.

2. Conor McGregor vs. Chad Mendes (UFC 189)

The Fight That Made Him Interim Featherweight Champion

Originally slated to face featherweight king José Aldo, McGregor had to adjust on short notice after Aldo withdrew due to injury. In stepped Chad Mendes, a powerhouse wrestler known for shutting down strikers.

For two rounds, Mendes dominated with takedowns and ground control. But McGregor’s tenacity shone through. He weathered the storm, stayed composed, and once back on his feet, unleashed a barrage of strikes that overwhelmed Mendes. The referee called it in the second round—TKO for McGregor.

Key Moment: A final left hand followed by a vicious combination sealed the deal and earned McGregor the interim belt.

Why It Matters: McGregor proved he could handle adversity, adapt mid-fight, and rise to the occasion—qualities of a true champion.

3. Conor McGregor vs. José Aldo (UFC 194)

The 13-Second Knockout Heard ‘Round the World

One of the most anticipated bouts in UFC history ended in a flash. José Aldo, undefeated for a decade, came out emotional and aggressive. McGregor, calm and calculated, countered with a perfectly timed left hand.

Thirteen seconds. That’s all it took.

Key Moment: McGregor’s surgical counter-punch dropped Aldo instantly, sending shockwaves through the MMA world.

Why It Matters: This win crowned McGregor the undisputed featherweight champion and forever etched his name into UFC folklore. It was a moment of pure mastery and timing.

4. Conor McGregor vs. Eddie Alvarez (UFC 205)

Becoming the First Two-Division Champion

At Madison Square Garden, McGregor had the chance to make history—becoming the first fighter to hold UFC titles in two weight divisions simultaneously. Facing lightweight champion Eddie Alvarez, McGregor was at his clinical best.

He controlled the fight from start to finish, dropping Alvarez multiple times before finishing him with a brutal combination in Round 2.

Key Moment: Post-fight, McGregor stood holding both belts and delivered an iconic speech that has become part of UFC lore.

Why It Matters: This fight wasn’t just a win—it was a statement. McGregor proved he could jump weight classes and still dominate the best.

Why McGregor’s Victories Transcend the Octagon

Conor McGregor’s greatest wins aren’t just personal milestones—they’ve elevated the UFC globally. His charisma, fight IQ, and ability to perform under pressure make him unlike any other figure in sports.

From Dublin gyms to global pay-per-view stages, McGregor’s legacy continues to influence fighters, energize fans, and evolve the sport of MMA.

Looking Ahead

Despite the ups and downs of his career, Conor McGregor remains one of MMA’s most iconic figures. Every fight he takes on brings hype, controversy, and echoes of his legendary past.

What was McGregor’s most impressive victory? Share your thoughts in the comments, and dive into the UFC archives to relive these historic moments.