HOUSTON -- When LeBron James walks onto the court for Houston’s NBA All-Star Game Sunday, he’ll do so as the undisputed king of his sport.

Named the league’s most valuable player three times in the past four years, James is once again dominating the NBA and most likely headed for his fourth MVP award — two fewer than Michael Jordan — with presumably a long career still ahead.

But while James is the most valuable player in the NBA, he’s nowhere close to being the league’s highest paid. Of the 10 players voted into the starting lineup of Sunday’s All-Star Game, five earn more than James, whose salary for this season ranks 13th in the NBA.

James’ decision a while back to “take my talents to South Beach” was a case of trading dollars for victories. The league caps what teams can spend on salaries.

The bimonthly checks cut by team owner Micky Arison this year will equal a bargain come season’s end: $17,545,000.

Kobe Bryant of the Los Angeles Lakers, the league’s highest-paid player, will earn about $10 million more than that this season.

James understands he’s underpaid in the purest sense, but he also understands reality: He makes obscene amounts of money playing a game. Super-rich athletes who gripe about money seldom get much sympathy — witness the outpouring of scorn when golfer Phil Mickelson recently complained that increased taxes on high earners, coupled with California’s high tax rates, might force him to make “drastic changes” in his playing schedule.

James also makes a fortune in endorsements, from companies ranging from Nike to Sprite to Samsung to Dunkin’ Donuts.

Still, the obvious question remains: Considering not only James’ impact on the Heat, but also his overall contribution to the entire NBA, how much money could James command on the open market if there were no league-imposed economic constraints?

“Per year, if there were no salary-cap restrictions, I think he’s worth well over $100 million, easy,” said Shane Battier, the Heat’s heady forward and former Duke University schoolmate of Heat CEO Nick Arison.

That’s $100 million per year.

It’s an audacious and historic number, but considering James’ recent run of play, it’s not complete fantasy. James is performing at a historic level of excellence. After thoroughly wiping the court in Oklahoma City on Thursday, scoring 39 points, pulling down 12 rebounds and dishing out seven assists, James has scored at least 30 points in seven straight games.

The last player to accomplish that feat going into the All-Star break was Wilt Chamberlain back in 1963.

“This guy, LeBron James, he’s doing stuff that I’ve never seen,” said Hall of Famer Charles Barkley on Thursday night during TNT’s Inside the NBA. “He’s on another planet.”

Considering Barkley’s sharp criticism of James in the past, not to mention his history of going head-to-head with Michael Jordan during both men’s prime, that’s high praise.

But a market value of $100 million?

“Really, it boils down to the ego of an owner,” Battier said. “A lot of owners would pay just to have LeBron James on their team. I can think of a couple that would pay him, easily, nine figures per year.”

According to one numbers cruncher — John Vrooman, an economics professor at Vanderbilt University — Battier’s figure is an overestimation of James’ worth by about $60 million. Here is how his math works: Vrooman used an advanced metric known in the sports world as “win-share,” which assigns a number to each player on a team based on his contributions, both offensively and defensively, for a season. Last season, when James led the Heat to the championship, he had a win-share value of 14.5, which translates to 31.5 percent of the 2011-12 Heat’s 46 regular-season wins.