Vergil Ortiz Jr. will return on July 8 vs. Eimantas Stanionis now that he's recovered from rhabdomyolysis and discovered it was caused by long COVID, Ortiz told ESPN on Thursday.

The 147-pound contest - Ortiz's fourth consecutive in his native Texas - pits top-10 welterweights with plenty of power (Ortiz is No. 3 in ESPN's rankings; Stanionis is No. 6.)

The fight has already been postponed twice. It was set for March 18 before Stanionis, 28, underwent an emergency appendectomy in January in Lithuania. A second postponement came when Ortiz, 25, dealt with a recurrence of rhabdomyolysis, pushing the fight from its April 29 date.

According to the Centers for Disease Control, rhabdomyolysis occurs when damaged muscle tissue releases its proteins and electrolytes into the blood. These substances can damage the heart and kidneys and cause permanent disability or even death.

Ortiz (19-0, 19 KOs) said he was fully cleared last month after being treated by Dr. Juan Bautista in Fresno, California, who diagnosed him with long COVID following a battery of tests.

"I actually had a hunch that that's what it was, but I didn't know too much about it - I'm not a doctor," Ortiz said. " ... I've never felt this good in a good, maybe three or four years. ... I'm still training hard ... that was never the problem. ... I'm noticing that I'm not huffing and puffing and I just feel great overall. ... I can't explain how good I feel compared to how I was."

Ortiz, who received two shots of the Moderna vaccine, said he first contracted COVID during training camp for his July 2020 fight with Samuel Vargas, whom he knocked out in Round 6.

"I could not breathe," Ortiz said. "I was struggling to keep my composure during that interview right after the fight, man. But I could not breathe at all, and it just kept getting worse after that fight."

He was sick with COVID again ahead of his next outing, a seventh-round KO of Maurice Hooker in March 2021. After the fight, Ortiz's father and trainer, Vergil Ortiz Sr., said his son's skin turned red.

"I wanted to call [the fight] off, and he didn't want to call it off," said Ortiz Sr. "He pretty much begged with me, and he promised he me that he would beat this guy and not to call it off. So, what do you tell your boy who's training through COVID and looking drunk and dizzy because he's so sick. ... I could see it in his body and his muscles ... it was attacking his muscles."

Ortiz contracted COVID a third time afterward, and in March 2022, was forced to withdraw from a fight vs. Michael McKinson after he was hospitalized with rhabdomyolysis.

Ortiz went on to score a ninth-round TKO of McKinson in August and hasn't competed since. During that time away from the ring, Ortiz heard the claims on social media that his condition was because he overtrained or simply couldn't make 147 pounds anymore.

"It can be mentally draining sometimes, I'm not going to lie," Ortiz said. "It's very frustrating sometimes ... when they're speaking on something that they don't know, but I mean, that's just how life is. And luckily, I try to keep a positive mentality and just try to ignore all the buzz and noise outside and just focus on myself."

Ortiz Sr. said it was difficult to know it was COVID because his son was nearly lapping the other fighters on their five-mile runs. "He's so used to pushing through it," Ortiz Sr. said.

Chicago Blackhawks star Jonathan Toews missed two months of the NHL season due to the effects of long COVID (and chronic immune response system) before he returned for the final seven games.

Ortiz is ready to return, too, after he was treated by Dr. Bautista for one month in Fresno, California. The doctor, who has a medical degree from Northwestern University, said Ortiz is 100% following a treatment plan that included flushing Ortiz's system with fluids, a hyperbaric oxygen system, and thrice-a-week IVs that delivered antioxidant-rich nutrients like vitamin C and magnesium.

"It was not at all due to overtraining ... the reason Vergil developed rhabdomyolysis is because he had a very tough bout of COVID," said Dr. Bautista, who practices integrative medicine at Bautista Health & Anti-Aging. " ... It's an inflammatory disorder.

"With athletes, we tend to see that inflammation on the heart. We tend to see that inflammation on the muscles. ... Vergil took some time off, but that didn't cure or take care of his inflammation."

Ortiz's inflammation levels were examined via a creatine kinase (CK) test, which measures the amount of creatine kinase in the blood. Dr. Bautista said that anything above 200 is abnormal, and that Ortiz's CK levels were approaching 4,000.

Following the one-month treatment program, Dr. Bautista continues to measure Ortiz's CK levels weekly to ensure the inflammatory markers aren't returning. The levels dropped from 4,000, to 400 to under 200 and finally, normal.

Ortiz uses the hyperbaric oxygen chamber daily and removed many inflammatory foods from his diet. He's now in training camp in Southern California ahead of his toughest test yet, a July 8 fight vs. Stanionis (14-0, 9 KOs).

"I've been so inactive, it's depressing when you're just at home and you feel like a bum and you know you should be out there," said Ortiz. " ... I'm trying to show them that I'm here like I never left."