NEW YORK – Quinton Jackson hasn’t exactly been keeping close tabs on Wanderlei Silva’s career, but he does have a pretty straightforward breakdown of their upcoming tetralogy.

“A lot of stuff changed,” Jackson told MMAjunkie collaborator Amanda Salvato on Tuesday. “I’m bigger now. He looks smaller. I think we both went in opposite directions in weight. I think that’s one thing that’s changed.”

Jackson (37-13 MMA, 4-2 BMMA) says he hasn’t seen that much improvement in Silva’s (35-13-1 MMA, 0-1 BMMA) game – wrestling included. But he also believes Silva is still a dangerous fighter.

On his end, “Rampage” has been working “on a lot of different stuff.” And that’s pretty much all he can share about where the two stand, almost 10 years after their last in-cage encounter.

“I didn’t notice anything,” Jackson said. “I don’t study the guy.”

The veterans are set to meet in a heavyweight bout on Sept. 29, at SAP Center in San Jose, Calif. The event, which has yet to be numbered, will stream exclusively on DAZN as part of a new deal with the streaming service.

The rivalry between “Rampage” and Silva dates back almost 15 years. The first time the two met, Silva was the winner via first-round TKO – a referee stoppage that, Jackson stresses, he doesn’t count as a knockout. The rematch, a year later, didn’t go much better for Jackson, who at least went an extra round before being knocked out.

When it comes to those displays, both under the PRIDE banner, “Rampage” is quite frank.

“Hey, it’s no lie, he gave me two of the worst ass-whoopings I ever had in this sport,” Jackson said. “I was a young fighter. And I learned a lot from that.”

That much was apparent in the fights that followed. Jackson fought another nine opponents, beating seven of them, before a trilogy with Silva. This time, they met in the UFC, and Silva was the one who ended up on the unfortunate end of a first-round knockout.

“I was really proud of myself, because I always knew that I could beat Wanderlei if I had the right training and stuff,” Jackson said. “This time, I have a great team behind myself again, so I see the (fourth) fight going in my favor again.”

Now, in a bout that most fight fans doubt would ever come to fruition, the former UFC 205-pound champion gets a chance to settle the score.

And it comes after a lot of career turns for both men. Since their last encounter, Jackson fought another 14 times. Those include a UFC title challenge and six Bellator battles – including one that took place outside the cage, as “Rampage” and the promotion engaged on a legal battle. He’s now on a two-fight skid, having lost decisions to Muhammad Lawal and Chael Sonnen.

Unlike “Rampage,” who’s been able to fight at least once a year since then, Silva has been somewhat inactive. He fought another six times for the UFC, with wins over ex-champ Michael Bisping, Cung Le and Brian Stann – whom Silva met in a historic barnburner.

Silva’s most recent cage appearance was also a decision loss to Sonnen. The two meet last June, at Bellator NYC, in a bout that was years in the making. The encounter snapped a long layoff for Silva, who was given a three-year ban by the Nevada Athletic State Commission after evading a drug test.

Silva, who admitted to having a banned diuretic in his system then, later announced he was retiring in light of his disappointment with the UFC. He was later granted his release from the promotion, however, and went on to sign with Bellator.

In calling for a tetralogy with the longtime foe last year, “Rampage” was not shy about accusing Silva of being on steroids in his foe’s two PRIDE wins over him. But, now that the fight is here, Jackson says he knows – or cares – very little about Silva’s turbulent recent history.

“I’ll be honest, I don’t follow Wanderlei’s career,” Jackson said. “I didn’t even remember that he was banned from the sport until you brought it up. I forgot about it. I heard something on the news, but – it’s sad to say, but I’m not a huge MMA fan anymore. I don’t really watch it that much anymore. So a lot of stuff goes on that goes past me that I don’t know about.

“You’ve got to respect other fighters, because we do what not many human beings do. Coming into this sport, I was a big fan of Wanderlei Silva because of his fighting style, and you’ve got to respect him for that – no matter what he does in sports and life, getting banned for whatever he got banned for. I could care less. None of that’s going to matter to me when I get in the cage with him.”

This bout, Silva said, could be the last of his MMA career, as he begins his steps into politics in Brazil. And while “Rampage” isn’t going around saying that this time around, he has publicly entertained the thought of maybe hanging up his gloves in the past.

“Rampage” hasn’t been one to shy away from voicing his disillusionment with some aspects of the sport, notably the style of fighting that simply does not appeal to him anymore. But, when it comes to retirement thoughts, that’s not what was behind them.

What is that, then?

Well, make what you will of Jackson’s lengthy answer to that.

“One of the reasons I’ve been thinking of retirement is, my body’s beat up and I’m 40,” Jackson said. “In this sport, when you get older, you notice that your time is coming to an end. If I was a lawyer or a doctor, I wouldn’t even be thinking about retirement at 40. I’d just be getting good. But as as an athlete, I’ve been thinking about retirement since 33. I still love competing. There’s been years where I stopped loving training, now I found love for training again. I still love competing, I just don’t enjoy watching the fights.

“I don’t want fans to take this the wrong way: Even when I got to the fights, to support my friends and stuff, even that can be like a chore. When I go to the fights to watch the fights, that’s when I want to go as a fan. And support my friends. Like Cheick Kongo, or Everett Cummings, one of my teammates. I haven’t been able to make it to any of his fights, because I’m dreading sitting there with the fans and trying to enjoy his fight and have to take a thousand pictures and autographs and stuff. I love ‘Rampage’ fans. I don’t love all MMA fans, but I do love my fans.

“Sometimes, you’re at a fight, it’s kind of a hard to distinguish the two. Everybody that ask for your picture, your autograph, aren’t your fans. They just know who you are. And you can kind of tell that sometimes, once you meet them, sometimes you just want to watch the fight with them and enjoy like they do. They wouldn’t understand that unless it happened to them. I don’t expect for fans to understand that. That’s another thing that I deal with. Every fighter’s different. Some fighters love the attention. I would just rather them say, ‘What’s up,’ give me a high-five, keep going.’ Instead, they want your attention, you’ve got to talk to them for a couple of minutes. And the fight be going on and you miss your friends fight.”

To hear from Jackson, check out the video above.

And for more on Bellator: Mousasi vs. McDonald, check out the MMA Rumors section of the site.