Canelo Alvarez became the first super middleweight undisputed champion in the four-belt era by defeating Caleb Plant by 11th-round KO Saturday night at the MGM Grand Garden Arena in Las Vegas.

Alvarez (57-1-2, 39 KOs), 31, of Guadalajara, Mexico, is a four-division world champion. He won the WBA and WBC belts in December with decision victory over then unbeaten Callum Smith. He then added the WBO title with a TKO victory against Billy Joe Saunders in May in Arlington, Texas.

Plant (21-0, 12 KOs), 29, of Nashville, Tennessee, defeated Jose Uzcategui in 2019 to win the IBF strap, and had defended the belt three times, before losing to Alvarez.

Full recap coming up ...

Round-by-round analysis:

Round 10: Caleb Plant has shown good defense and movement, attributes we knew he had going in. What he hasn't shown is a willingness to really go for it in a fight he's losing. 10-9, Canelo. 98-92, Canelo.

Round 9: Plant, at long last, unloads with a big combination at the end of the round, but it wasn't enough to win the round. Alvarez continues to pin Plant in the corners where he inflicts punishment. 10-9, Canelo. 88-83, Canelo.

Round 8: Caleb Plant barely throwing right hands, content to make Canelo miss and jab. Alvarez, meanwhile, continues to apply the pressure and throw body shots. If Plant could make Canelo pay with a few counter shots, he could take some of these rounds. 10-9, Canelo. 78-74, Canelo.

Round 7: Alvarez is pouring it on now and just crushing Plant to the body. Caleb will answer with a solid counter right, but they're too few and far between. Alvarez cruising to victory. 10-9, Canelo. 68-65, Canelo.

Round 6: Canelo Alvarez is rolling now. He battered Plant in that round, with plenty of right hands to the body that made the area red, and with a bunch of big left hooks up top. Plant not throwing any power shots with the right hand. 10-9, Canelo. 58-56, Canelo.

Round 5: Caleb Plant making Canelo miss but not making him pay. Alvarez landed a big left hook to the face in that round, and his relentless pressure is winning the fight with Plant not able to land anything of consequence. 10-9, Canelo. 48-47, Canelo.

Round 4: Big round for the Mexican star, who landed a bundle of big shots, most notably the left hook (both to the body and head). Alvarez pressed him to the ropes more than the first three rounds, and as usual, is coming on after a slow start. 10-9, Canelo. 38-38.

Round 3: Caleb Plant boxed beautifully, doubling and tripling up on the jab to keep Alvarez at bay. Plant used the jab to set up lefts to the body and stayed away from any danger. So far, Alvarez only attacking in bursts once he has Plant on the ropes. 10-9, Plant. 29-28, Plant.

Round 2: Caleb Plant was far more effective in the second, using feints to set Canelo up for the left hand, both with the uppercut and to the body. Alvarez ended the round with an effective three-punch combination, but it's all even. 10-9, Plant. 19-19.

Round 1: Canelo Alvarez didn't throw a punch over the first 90 seconds as he applied pressure and tried to measure Caleb Plant's timing, but he connected with a few solid body shots over the second half of the frame to eke out the round. 10-9, Canelo.

• Now is Canelo's turn to walk to the ring. Mana's lead singer Fher Olvera is walking with Canelo while singing "El Rey" a song by the legendary Vicente Fernandez. Canelo is wearing a gold robe with white gloves.

• Caleb Plant is on his way to the ring wearing white trunks, white Grant gloves and a white robe. The scar under his right eye suffered during an altercation with Alvarez at a press conference to officially announced the fight in September is still visible. Can that be a factor?

Results:

Dirrell scores must-see KO over Hernandez

Anthony Dirrell uncorked a hellacious right uppercut to score a highlight-reel knockout of Marcos Hernandez in Round 4 of their clash in the co-feature of Canelo-Plant.

The former super middleweight titleholder floored the journeyman with the single punch that he loaded up on. Hernandez barely beat the count, but he was on wobbly legs and referee Celestino Ruiz stopped the contest 22 seconds into the round. The victory is Dirrell's first since February 2019, when he won the vacant super middleweight title vs. Avni Yilidirm.

Dirrell (34-2-2, 24 KOs) was coming off a disappointing split draw with Kyrone Davis in February, and before that, lost his title via ninth-round KO to David Benavidez in September 2019. The 37-year-old native of Flint, Michigan, is a cancer survivor. He's rated No. 10 by ESPN at 168 pounds.

Hernandez (15-5-2, 3 KOs), a 28-year-old from Fresno, California, has won just two of his last seven bouts.

Vargas returns with one-sided decision victory

Rey Vargas, in his first fight at 126 pounds, ended a career-long layoff with a unanimous decision victory over Leonardo Baez. Two judges scored it a shutout, 100-90, with a third tallying it 99-91.

The 30-year-old Mexican used his uncanny height and reach for the division to keep Baez at the end of his punches in a lackluster affair that featured little action.

Vargas (35-0, 22 KOs) made five successful defenses of his 122-pound title before a fractured leg sidelined him and forced him to give up that belt; this was his first bout since July 2019. Now at featherweight, he'll seek to win a title in a second weight class.

Baez (21-5, 12 KOs), a 26-year-old Mexican, has lost three of his last six bouts.

Rodriguez returns to winning ways with KO of Romero

Elvis Rodriguez, on the heels of his first professional defeat, rebounded with a fifth-round KO of Juan Pablo Romero in the Canelo-Plant PPV opener.

The 25-year-old from the Dominican Republic floored Romero in Round 4 with a left cross and then finished him in the following round with the same punch. Rodriguez (12-1-1, 11 KOs) opened Romero's guard with a right uppercut that missed before the left hand connected flush.

Romero (14-1, 9 KOs) sat on the canvas and watched as the referee reached the count of 10 with one second remaining in the round.

Rodriguez was released by Top Rank following an upset decision loss to Kenneth Sims Jr. in May. But in his PBC debut, Rodriguez proved that he's still a prospect to watch at 140 pounds. He's trained by Hall of Famer Freddie Roach, and despite his defensive flaws, Rodriguez possesses the power to finish a fight at any moment.

Romero, 31, represented Mexico at the 2016 Olympics.

Diaz scores fifth-round KO of Salvatierra

Fernando Diaz capped the Canelo-Plant prelims with a vicious fifth-round KO of Jan Salvatierra.

Diaz (10-1-1, 3 KOs) connected with a left hook that floored Salvatierra (7-1, 3 KOs), who attempted to beat the referee's count only to fall down a second time. The bout was waved off at 2:16 of Round 5.

The junior bantamweight from Riverside, California, handed Salvatierra, who is from Mexico, his first pro loss in what was a competitive battle until the finish.

Velazquez stays undefeated with decision win over Mendoza

Joselito Velazquez remained undefeated with an eight-round shutout unanimous decision over Gilberto Mendoza. All three judges saw the fight identically: 80-72.

Velazquez (14-0-1) was effective with his attack to the body in a fight that featured little action. The 112-pounder Mexican was fighting for the first since May, when he suffered the lone blemish on his record (a draw).

Mendoza (19-11-3, 10 KOs) also has decision losses to Angel Acosta and Rau'shee Warren.

Meza recovers from knockdown to get decision win

Jose Antonio Meza survived a first-round knockdown to score a major upset in a 130-pound bout. All three judges scored the fight the same: 76-75.

Meza (8-6, 2 KOs) boxed from the outside after he was nearly stopped in Round 1. The 25-year-old Mexican had lost three of his last four bouts. Jose Gomez (12-1, 5 KOs) was fighting for the first time since November 2019. And now, he's suffered his first pro defeat.

Barthelemy stops Vittori in Round 2

Former two-division champion Rances Barthelemy scored a second-round knockout of Gustavo Vittori in a junior welterweight bout, as he looks to climb the ranks and get a second shot at a title in a third weight class.

The 36-year-old Cuban fighter, who held world titles at 130 and 135 and unsuccessfully challenged for a world title at 140, handled the Argentine journeyman with ease in a total mismatch to kick off the Canelo-Plant prelims.

Barthelemy (29-1-1, 14 KOs) hasn't boxed in a notable bout since a lackluster draw with Robert Easter Jr. in April 2019, a Showtime main event. Vittori (25-10-1, 12 KOs) has now lost eight of his past 13 fights.