Ernesto 'Tito' Mercado isn’t breathing heavy, but you can’t miss the sound of footsteps as he conducts an interview five days before his Saturday bout against Carlos Manuel Portillo.

“Are you doing roadwork,” I ask.

“Yeah, a little bit,” he laughs. “Always working.”

At the time, he was already six miles into his run, with two to go. Call it attention to detail, but after going the distance for the first time in his career last month against Xolisani Ndongeni and feeling it after a few rounds, he’s leaving nothing up to chance when he faces Paraguay’s Portillo in Ontario, California.

“After the second round, I was already asking my corner, ‘What round is it?’ because I was tired,” said Mercado. “But knowing that I was fatigued and to be able to hurt him in any round that I wanted to, it just shows that my punch, it doesn't fade away; it carries. But I was making some fundamental mistakes that I shouldn't have. I definitely knew I had him hurt a couple times and I could have took him out, but I just wasn't a hundred percent that day.”

Instead, Mercado improved to 11-0 with 10 knockouts and learned some valuable lessons from the durable South African veteran, who entered the ring with a 31-2 record. One, you’re not going to knock everyone out. Two, adjusting to an awkward style requires a high Fight IQ and being able to adjust on the fly. And three, knowing what you’re walking into when it comes to a fight’s location is key, and while fighting in his father’s native Nicaragua was a line to scratch off the bucket list, it also presented some issues that showed up when he stepped between the ropes.

“Obviously, I fought somewhere out of my comfort zone as far as climate and all that in Nicaragua,” said Mercado. “I definitely felt the weather over there, so I kind of got a little fatigued. But to be able to know that I pushed through 10 rounds, being fatigued and out of my comfort zone and fighting a guy that knows what he's doing, I think I learned a lot from that fight.”

And for the record, Mercado beat Ndongeni via three identical scores of 99-91. Not bad for a tough night at the office, which shows you that the 21-year-old from Pomona is his harshest critic, and one of the top prospects in the sport. And someone who takes what he learned from that fight and is applying it in preparation for his fourth fight of 2023. That’s being honest with yourself, something not too many boxers are willing to do, and Mercado doesn’t hesitate to admit that going back to your corner after the second round and hoping he only had one or two to go wasn’t easy.

“It's not a great feeling knowing that you're tired in the ring,” he said. “But there was no part of me that wanted to quit or fold. I did what I had to do. The guy tried to push forward strong, and my corner told me to box, and I knew that if I didn't push, he was going to steal some rounds from me. So I picked it up and did what I had to do to get the victory and it was pretty lopsided. Being fatigued, it's a new experience for me, so to be able to go through that and keep winning, once I go to a world championship fight, I know I've been through everything.”

Some might say with 11 pro fights, a championship fight is a ways away for Mercado. But he feels that he’s ready, and with another couple 10-rounders under his belt, 2024 isn’t a far-fetched notion given his talent. And after flying under the radar for much of the time since he turned pro in 2021, the buzz is starting to build and he’s noticing it – good and bad.

“Even the negative comments, I feel like those are a good thing, as well, because like my father told me, whether it's good or bad, they're still talking about you,” Mercado said. “So even the bad comments, I don't take 'em as bad comments no more, whether they're critiquing how I throw punches or critiquing just any single thing, I look at it and I make it into a positive. But I definitely do think they're talking about me more, and I'm definitely getting ranked a lot higher, so I know these guys that are world champions, they're starting to see me.”

And Mercado is looking right back at them, confident that one day this early homework will pay off down the line.

“I've been looking at everybody from 130 to 147, because all of them could potentially be opponents, so I'm always watching these guys,” he said. “That's why I hope a lot of these guys get ready because I don't know if they think I'm watching them, but I’m coming for every single one of them. There's obviously a lot of great talent from 135 to 147 and to be able to have a type of performance like Crawford did with Errol Spence, where he made it so one-sided, that’s the thing I want; I want to make the special guys look average and I just want to be the best at what I do. To me, it's not about fame. I just want to be recognized for what I do, and it's more for myself to know that I'm the best.”

Mercado’s voice speeds up, the excitement level rising, and it has nothing to do with knowing he only has two miles left to run for the day. It’s because he’s ready for this yesterday, at least in his mind, and even though the realist in him knows it won’t be coming as fast as he wants it to, he is confident that world title fights and championships are around the corner.

“The more wins that I rack up, it gets more exciting,” he said. “The hardest part about it is waiting because I know I'm right there, but even waiting another year, you’re anxious because I want to get in there already. But I guess the part I've been learning a lot is having patience. I know my time's going to come, most likely probably next year, so I've got to wait a couple more months to next year and then it's my time to shine.”

But first, there’s Carlos Manuel Portillo and the biggest fight of his career. Why? Because a loss at this point for a hot prospect will cool things down considerably. Mercado wins? He moves forward. He stumbles? Then he’s not talking about title fights in 2024. Luckily for him, he knows it, and he’s prepared accordingly.

“In boxing, it’s real critical,” he said. “It's not like other sports. In the NBA, you can lose a game and they still got high hopes for them. In boxing, you kind of lose your value and you step back like 10 steps. So every fight, to me, is important. Even when I was fighting my debut, when I was fighting against guys that I knew couldn’t beat me, if they made me look bad, I knew that it could potentially set me back. So, yeah, I'm training hard for every fight like it could be a title fight because I know eventually it'll lead to one. But, in order for me to get to that, I know I got to pass this test first.”