The NBA banned Toronto Raptors forward Jontay Porter for life on Wednesday after a shocking examination discovered he bet on league matches, termed a “cardinal sin” by NBA commissioner Adam Silver.

The league added that Porter, who spent part of his season in the NBA and part of it in the developmental G League, allegedly communicated sensitive information about his fitness with a sports bookmaker and pulled himself from a game to influence betting on his own play.

“There is nothing more important than protecting the integrity of NBA competition for our fans, our teams and everyone associated with our sport, which is why Jontay Porter’s blatant violations of our gaming rules are being met with the most severe punishment,” Silver said in a statement announcing the ban.

The league stated its investigation remains open and it is exchanging evidence with federal prosecutors regarding the incident.

The NBA initiated an investigation against Porter, younger brother of Denver Nuggets star Michael Porter Jr., in March following accusations of abnormal betting patterns in games he was engaged in.

The 24-year-old has not played since March 22, soon before an ESPN investigation disclosed details of possible violations in games in which he featured.

The league said it discovered that prior to the Raptors’ March 20 game, Porter gave private information about his personal health state “to an individual he knew to be an NBA bettor”.

The league continued: “Another individual with whom Porter associated and knew to be an NBA bettor subsequently placed a $80,000 parlay proposition bet with an online sports book to win $1.1 million, wagering that Porter would underperform in the March 20 game.”

In that same game, Porter played just three minutes before declaring that he felt ill. “Due to the unusual betting activity and actions of the player, the $80,000 proposition bet was frozen and was not paid out.”

In addition, the league said Porter placed at least 13 wagers on NBA games from January through March of this year while traveling with either the Raptors or their G League franchise, the Raptors 905.

He used an associate’s online betting account to make wagers ranging in value from $15 to $22,000 for a total of $54,094, which resulted in net earnings of $21,965.

None of the bets involved any game in which Porter played, but three of the bets were multi-game parlay bets that included one Raptors game and he bet on the Raptors to lose.

Porter played in 26 games, including five starts, for the Raptors this season, averaging 4.4 points and 3.2 rebounds.

Raptors president Masai Ujiri, speaking to reporters at an end-of-season press conference on Wednesday, said the inquiry took him by surprise.

“You don’t want this for one of the kids; you don’t want this for our team; and we don’t want this for our league,” Ujiri said. “That’s for sure.

“You prepare for all kinds of situations in the NBA, but you definitely didn’t see this coming,” he added. “But we act in accordance with what the NBA rules and regulations are for dealing with things like this and we move forward with it.”

Since the US Supreme Court struck down a federal ban on sports gambling in 2018, a majority of US states have legalized online sports betting, and pro sports leagues have enthusiastically partnered with the industry to continue to bar their players from betting on their own leagues and otherwise restrict how they can wager.

Days before Porter’s scandal arose, Major League Baseball was stunned when Dodgers superstar Shohei Ohtani accused his longtime interpreter and buddy Ippei Mizuhara of taking millions from him to pay off illegal gambling debts.

Mizuhara has been charged with felony bank fraud after allegedly stealing more than $16 million from Ohtani, who has not been implicated in any illicit gaming.

The NFL punished Denver Broncos defensive end Eyioma Uwazurike for a season for betting on games and meted out a handful of shorter penalties for milder transgressions, such as making bets on other sports while at team facilities.

Silver has been an advocate of legalizing and regulating sports wagering but said in Wednesday’s announcement that the Porter case indicated that extra regulatory measures may be needed.

“While legal sports betting creates transparency that helps identify suspicious or abnormal activity, this matter also raises important issues about the sufficiency of the regulatory framework currently in place, including the types of bets offered on our games and players,” Silver said.

“Working closely with all relevant stakeholders across the industry, we will continue to work diligently to safeguard our league and game.”