SACRAMENTO, Calif. >> Demetrious Johnson had a little something to show anybody who still doubts the UFC’s small guys can produce big knockouts.

Johnson stopped Joseph Benavidez with a devastating right hand in the first round Saturday night, defending his UFC flyweight title and capping a dominant year for the 5-foot-3 champion known as Mighty Mouse.

With his third win of the year, Johnson (19-2-1) remained the only champion in the history of the UFC’s lightest men’s division. But he did it in a fashion almost nobody expected, catching Benavidez (19-4) directly in the face with an unblocked punch and knocking the challenger senseless 2:08 into the fight.

“A lot of people say I don’t have knockout power, but I’m always getting better,” Johnson said. “I just let it go, and I was happy to get the finish.”

Local favorites Urijah Faber and Chad Mendes also won on a card stacked with mixed martial artists from Northern California, but Johnson — from the Seattle area — silenced Benavidez’s hometown crowd by winning a rematch against a fighter who inspired him to get into the sport.

Benavidez appeared to be out cold before he hit the canvas, and Johnson landed several additional punches before the referee stepped in.

Johnson beat Benavidez by split decision in Toronto 15 months ago, claiming the UFC’s first flyweight title in a tight matchup. Johnson defended his title twice earlier this year against John Dodson and John Moraga, but Benavidez earned his way back to a title shot with three straight victories this year, the last two by impressive stoppage.

“If people want to see me as the best pound-for-pound fighter in the world, that’s totally fine,” Johnson said. “My job is to go back in the gym and keep working. It was a great year for me. Had a couple of great fights, and I’m happy to come away with this knockout. … It would be awesome to be the fighter of the year for 2013, but my goal is just to keep on getting better and win fights.”

Faber stopped Michael McDonald in the second round, knocking the younger bantamweight into the side of the cage with punches before finishing with a guillotine choke. Mendes fought off an illness to beat Nik Lentz by decision. Lightweight Joe Lauzon opened the televised card by beating Mac Danzig in a bloody unanimous decision.

Faber (30-6) was fighting in his hometown for the first time in nine bouts since April 2010, and for the first time under the UFC banner. He was a champion in the lighter-weight WEC promotion before it was absorbed by the UFC, and he appears to be rounding into championship form again in the 135-pound division.

“People say I’m old, but I’m 34,” Faber said. “Look at what people are doing in their 40s and 50s, and it’s amazing. The guys on my team prepared me so well for this fight that I never doubted I would get the victory.”

The Sacramento crowd roared throughout Faber’s ring walk to his trademark song, 2Pac’s “California Love,” and they actively booed McDonald, who’s from nearby Modesto. Faber took charge from the opening moments, controlling the fight on the ground and in standup.

Faber caught McDonald with punches early in the second round and again midway through the round, knocking his stumbling opponent of the side of the cage with the force of his blows. Faber pounced on the prone McDonald and finished it with one of his trademark chokes, thrilling the crowd.

“There is a real sense of community here in Sacramento,” Faber said. “We have a lot to cheer about, and I’m glad I get to play a role in that. Michael McDonald is a tremendous opponent and I really look forward to watching his career. He’s got so much potential, but tonight was my night.”

McDonald (16-3) has lost two of his last three bouts, also losing by submission in a title shot against Renan Barao in February.

Mendes (16-1) won without much flair, controlling the first round and largely coasting through the final 10 minutes against Lentz (26-6-2). Mendes, who had stopped his last four opponents, said he had a sinus infection.

“After the first round, my lungs felt heavy,” Mendes said. “But I just had to power through it. I hit Lentz hard, about as hard as any guy I have ever fought. He kept bouncing back.”

Lauzon (23-10) won every round for just his second victory in his last five fights, leaving Danzig (22-12-1) with a bloody face and a badly damaged nose after his fourth loss in five bouts.

Canadian lightweight Sam Stout won every round in an early decision over Cody McKenzie, who fought in plain white shorts with pockets — and the price tags still attached until referee Herb Dean ripped them off. McKenzie forgot his shorts at his hotel and had to buy a new pair outside the arena.

“That’s one of the weirdest things I’ve ever seen, and it’s even weirder that we let it happen,” White said.