Gesias Cavalcante, who may be the best fighter in the business that nobody but the most ardent mixed martial arts fan has ever heard of, could change his popularity status Saturday night with his first appearance on a nationally televised event.

Cavalcante has spent the past four years fighting with Japan's K-1 MMA organization, winning the Hero's middleweight (154-pound weight class, essentially the same as the lightweight division in North America) tournament and championship in both 2006 and 2007. But his real name wouldn't be familiar to fans in Japan either, since he went by the easier-to-promote moniker "J.Z. Calvan."

"I had a good career in Japan," said Cavalcante. "My last fight in the U.S. was in 2006 in Los Angeles [at the Los Angeles Coliseum, where he beat current 'TUF' fighter Nam Phan in 26 seconds]."

On Saturday, Cavalcante and former Strikeforce lightweight champion Josh Thomson battle in a key match in a Showtime event at HP Pavilion in San Jose, Calif. Welterweight champ Nick Diaz will headline the four-match television special in a grudge match against K.J. Noons.

While Cavalcante and Thomson have entirely different styles of fighting, almost a power-vs.-speed matchup, they also have a number of things in common. Both have been top 10 in the world at times in recent years, as well as champions in major organizations. The two have almost identical records: Cavalcante sports a 17-3-1 record with one no contest; Thomson's record is 17-3, with one no contest. But their biggest similarity is their battles to remain healthy.

Cavalcante, 27, had major operations on both knees, and has fought only twice in the past two and a half years. Thomson, 32, suffered a broken ankle 18 months ago, while holding the Strikeforce title. He injured it a second time while getting ready for a title defense with Gilbert Melendez, from whom he won the title in a shutout decision on June 27, 2008, in San Jose. The rematch was postponed a few times before Thomson lost the title via decision on Dec. 19, 2009, in one of the best matches of the year.

Since Thomson's return, he's continued to suffer injury. Both of his hands were damaged in the Melendez match, which he attributed to a rushed hand-wrap before the fight, combined with the output of punches landed. The fight was so brutal that when asked about a rematch, both fighters have stated that while they wouldn't turn it down, they also dread it because of how much punishment they took in the five-round war.

Thomson then suffered broken ribs on the first takedown in his last fight vs. Pat Healy on June 26, when he scored a come-from-behind submission win.

Thomson's training camp has been tough, between waiting for his ribs to fully heal, dislocating two fingers at two separate times – which limited his stand-up training early on – and ongoing shoulder problems.

"It's been a rough camp," said Thomson. "I've been battling nagging little injuries. Until the last several days, I wasn't feeling in shape. This last week things have started to look better. I've got the spring back in my step."

Thomson was rightly worried in recent weeks about his performance, noting he was being outwrestled and out-struck in training sessions by people who usually couldn't do that to him, but his physical improvement has improved his attitude.

Because of the injuries, both fighters have come to the same conclusion recently about their training, which Cavalcante calls, "less is more." Thomson noted taking a day off to rest helped him recuperate better, and he's on target leading into Saturday.

Cavalcante, who believes his mental determination has been one of his best weapons as a fighter, led him to overtraining that wore out both of knees due to his style. His mentality used to be that he would do all his coaches would tell him to do, and when that was over, he'd continue to train on his own.

Thomson has nothing but good things to say about his opponent, who has never been stopped in his career, including going into a risky 2007 kickboxing match in Japan against Masato, the best Japanese fighter in that sport of this generation.

"He's very tough," said Thomson, putting the emphasis on "very." "He went the distance with Masato in a kickboxing match. Look at his only losses, [Joaquin] Hansen, [Shinya] Aoki and [Tatsuya] Kawajiri, when all three were top 10 in the world."

While on paper, one would assume the winner of Saturday's fight would be next in line for a shot at Melendez, who has been out of action since April nursing a broken hand, but there are a lot of variables.

Strikeforce CEO Scott Coker noted that K-1 is hoping to get Melendez for its annual New Year's Eve event. In September, they were pushing for a Melendez-vs.-Shinya Aoki rematch of the April 17 match on CBS that Melendez took via one-sided decision with the Strikeforce title at stake.

The idea would be for the rematch to be held in a ring, possibly with Aoki's Dream title at stake.

But neither fighter appeared to be thinking about a possible title match heading into Saturday's fight. Cavalcante has a unique attitude among fighters: He doesn't dwell on the past, and doesn't look that far into the future. Even though he's been a champion, the belts themselves don't seem to motivate or define him.

When K-1's MMA organization changed from being named "Hero's" to "Dream," he lost his middleweight championship in the changeover as the new organization was creating its own title. He said that didn't concern him. In his first match of the tournament, facing local favorite Aoki, the match was stopped when it was ruled Cavalcante threw illegal elbows to the back of Aoki's head, knocking him out and rendering him unable to continue.

Cavalcante had dominated the short fight up until that point. The replays seemed to indicate the blows landed in a legal position, and people questioned if Aoki was looking for a way out. It was a fairly big controversy at the time, but Cavalcante said he doesn't even think about it anymore.

"I don't think about the past," he said.

Aoki won the rematch by decision and ended up taking the entire tournament. But even if Cavalcante had won that first match, his knees were starting to give him problems. He tried to avoid surgery after tearing his ACL, since other fighters had done so.

He said his knees have been fine ever since, but in not coming back until 13 months later, Cavalcante blamed ring rust on his decision-loss to Tatsuya Kawajiri.

It was nearly another 14 months before his most recent fight, a split-decision win over Katsunori Kikuno on July 10. That still stings today, as he has yet to be paid for that fight because of financial problems over in Japan, which is one of the reasons he's now fighting in Strikeforce.

Fighters who have made their names in Japan often face problems when they adjust to U.S. fighting. It's a different mentality, different rules and regulations, and the cage instead of the ring.

Thomson and Cavalcante both feel the ring-vs.-cage issue, which has hampered other fighters making the transition, won't be a factor here.

"I've always trained in the cage," said Cavalcante, who came from Brazil to Coconut Creek, Fla., and joined the American Top Team at age 19.

Thomson, who fights for the eighth time at the HP Pavilion in his home city of San Jose, thinks a key factor may be the crowd itself.

"He's used to the quiet Japanese crowd, and now he's going to be fighting before a crowd making a lot more noise," he said. "Will that give him an adrenaline boost, or will it cause an adrenaline dump? I don't know."