MANILA- The PBA, its medical consultant, and officials of Clark insist that the league's bubble has not been "breached," even after a player returned a positive result for COVID-19.

A Blackwater player was extracted from the bubble early Sunday morning and transferred to the Athletes' Village in New Clark City, which serves as a quarantine facility. The rest of the Elite are currently in isolation, as are the TNT Tropang Giga, whom they played last Thursday at the AUF Gym in Angeles City.

Blackwater's game against Rain or Shine, scheduled for Sunday afternoon, has been postponed.

Despite this development, the PBA assures that the bubble at Clark, Pampanga remains safe, and that they are prepared for incidents like this.

"Rest assured po, ako po ang nagsasabi po sa inyo, safe po ang mga players dito, and'yan po lahat ang medical experts, 'wag kayong mag-alala," PBA Commissioner Willie Marcial said Sunday.

Dr. Raul Canlas, the league's medical consultant, also said: "Everything is working. These incidents are, in a way, expected to happen… I just want to assure everybody that everybody's safe in the bubble. It's probably one of the safest places you can be in right now."

• READ: PBA player tests positive for COVID-19 in Clark bubble
• READ: Amid positive COVID-19 test, Blackwater 'staying calm'

The player's positive test came three days after a referee was tagged as a suspected positive case. The official worked a game between Blackwater and Alaska on Tuesday night, and was transferred to the quarantine facility on Wednesday morning.

Both Alaska and Blackwater still played their games the next day. The Elite's opponents, TNT Tropang Giga, are now in isolation as well.

Vince Dizon, the president of the Bases Conversion and Development Authority, stressed that all the protocols that they put in place are being followed.

"When we started doing the PBA bubble, we put in place several layers of protocols, consistent and benchmarked with the successful bubbles abroad, especially the NBA and the NFL," he said. "Ito 'yung mga naging successful bubbles sa US nitong mga nakaraang buwan."

Testing, said Dizon, is "only one component" of the protocols. Dizon, who is also the country's testing czar and deputy chief implementer of the COVID-19 task force, added that even an RT-PCR swab test is not 100% accurate.

"The protocols are in place, several layers of protocols, similar to what they have done in the NBA and other bubbles abroad. And we will just have to be very, very strict with the protocols," he said.

"But I think there is no reason to say that the bubble has been breached," he added, further pointing out that the referee who became the league's index case eventually tested negative in both an antigen test and a confirmatory RT-PCR test.

• READ: Games to push through after referee tests positive

The strict protocols that they are implementing, said Dizon, are precisely for these kinds of situations. In the lead-up to the restart of the PBA season, the PBA and the officials of Clark repeatedly stressed that they are ready should there be positive results.

"I just, again, wanna emphasize, what has happened to us in the past couple of days happened as well to other bubbles in the United States, both the NBA and the NFL, and we just have to follow the protocols that we have benchmarked and follow them properly," said Dizon.

No player returned a positive test in the NBA, which successfully completed its season in a bubble at the Walt Disney World Complex earlier this month. A Sacramento Kings player produced an inconclusive result in August -- what is called a "false positive" -- but was cleared after returning two negative results within 48 hours.

The NFL, meanwhile, was one of the American leagues that opted against a bubble. Instead, they decided to implement strict rules for teams, which included guidelines that limit players' mobility once they leave the team's arena.

There have been COVID-19 outbreaks among NFL teams already, with teams shutting down their practice facilities as a result.

Major League Baseball also opted against a bubble for its shortened regular season, but decided to hold the playoffs and the World Series in a bubble. Limited fans are currently allowed at the Globe Life Field in Arlington, Texas, where the Los Angeles Dodgers and the Tampa Bay Rays are playing for the championship.