The bizarre spiral of former middleweight champion Julio Cesar Chavez Jr.'s career continued on Saturday in Phoenix, Arizona. The culmination of what was a whirlwind promotion in which Chavez skipped out on a drug test (forcing the fight to switch states) and miss weight by nearly five pounds ended when Chavez quit on his stool after Round 5 against Daniel Jacobs and ran out of the ring while being pelted by garbage. 

The exact reason for Chavez quitting was never properly resolved as he ditched out on the post-fight interview amid a showering of boos from the Talking Stick Resort Arena crowd that had so aggressively cheered him each time he threw a punch. Chavez (51-4-1, 33 KOs) initially claimed to his corner that his hand was broken, though trainer Freddie Roach later told DAZN announcers it was his nose that caused the retirement. 

The fight was contested at a catchweight 173 pounds after Chavez, the son of the Hall of Fame Mexican legend, paid Jacobs one-third of his purse to keep the fight active after he so badly missed weight. Jacobs (36-3, 30 KOs) chose to accept the $1 million penalty rather than face Gabriel Rosado, who was placed on the undercard as a potential replacement should Chavez pull out for any reason. 

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Chavez, with his hair dyed blonde and blue, was a rock of granite and muscle when he entered the ring but appeared to be upwards of two divisions larger than Jacobs, who was originally expected to be making his super middleweight debut after losing a decision to Canelo Alvarez in their May unification fight at 160 pounds. Jacobs, 32, had difficulty dealing with Chavez's power in the opening round before adjusting nicely to flurry with body shots and quick combinations over the next four rounds.

"To me, it wasn't my debut at super middleweight because this is so disrespectful," said Jacobs while dodging debris in the ring after the right. "To me, he was a cruiserweight. Even his jab was heavy and his body. Physically, he was the bigger man in the show. I tried my best to be elusive and box but he was heavy. Slowly but surely I got my counter-punches in there, and he quit on his stool. He didn't let me enjoy my victory. I'm from Brownsville and I never ran and I never will."

Jacobs enjoyed his best work in the fifth and final round with a series of flurries that began after Chavez cracked him with a huge right cross that woke up the crowd. Jacobs took the punch well and landed counter combinations that caused blood to flow from Chavez's nose and a cut to open above his left eye. After the round, Chavez went back to his corner and asked out of the fight, giving Jacobs the bizarre TKO win.

"It took about two or three rounds because I didn't know what he had left," Jacobs said. "I didn't know if he was hiding something up his sleeve. This was the biggest opponent I ever had in my career, and I knew it was a matter of time before he got tired. I did my part. I know [the crowd] is not mad at me, they are mad at Chavez. But I don't get to enjoy this victory.

"I didn't fight a super middleweight, I fought a cruiserweight."

Although Jacobs appeared to be poised for a campaign at 168 pounds moving forward and did show interest in the likes of unbeaten titleholder Callum Smith, he didn't rule out a move back to middleweight for the right fight.

"I want to fight the biggest names in the division. I want to fight them all," Jacobs said. "Honestly, I want to fight Jermall Charlo or a 'GGG' [Gennady Golovkin] rematch, but if I can't get that, I'll fight at super middleweight."

Jacobs outlanded Chavez 61 to 35 overall, according to CompuBox, including 50 percent of his power shots. The 33-year-old Chavez suffered his first defeat since a lifeless decision loss to Alvarez in their 2017 pay-per-view bout. Two years earlier, Chavez asked out of a fight he was losing against light heavyweight Andrzej Fonfara in a 172-pound catchweight bout. Chavez, a former middleweight titleholder, has really never been the same since a 2012 title loss to Sergio Martinez that saw him score a miraculous knockdown in Round 12 after losing nearly every second of the fight. His career since then has been flooded with missed weight, drug suspensions and an overall lack of discipline.

In the co-main event, Julio Cesar Martinez and Cristofer Rosales put on an absolute show of a fight that ended with Martinez scoring a TKO win in the ninth round. The pair of flyweights brawled over the first 24 minutes of the fight before Martinez established himself and took over. In the opening bout, Maurice Hooker added another knockout to the highlight reel with a first-round stoppage of Uriel Perez.

CBS Sports was with you for every punch with our live scorecard and updates below. If you are having trouble viewing the results or want to refresh the scorecard, please click here.

Jacobs vs. Chavez scorecard

Round123456789101112Total

Jacobs

9

10

10

10

10

49

Chavez Jr.

10

9

9

9

9

46

Jacobs vs. Chavez results

Daniel Jacobs def. Julio Cesar Chavez Jr via sixth-round TKO (Chavez retired on stool)
Julio Cesar Martinez def. Cristofer Rosales via ninth-round TKO to win WBC flyweight title
Maurice Hooker def. Uriel Perez via first-round KO

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