The Arizona Republic reported in a story on its Web site Sunday that the coach will be fired Monday and replaced by assistant Alvin Gentry. The newspaper quoted multiple sources saying the decision had been made.
Porter told The Associated Press he hadn't heard anything from his bosses.
"I know they're meeting tonight," he said. "They're reviewing the whole system."
Owner Robert Sarver, general manager Steve Kerr and Gentry did not return messages left on their cell phones.
The Suns were attempting to avoid making news over the All-Star weekend being staged on their home turf. The franchise also is in talks with numerous teams about trading Amare Stoudemire, a starter in Sunday night's All-Star Game.
Porter is four months into a three-year, $6 million contract as the replacement for Mike D'Antoni, who left after four highly successful seasons to coach the New York Knicks.
Gentry has been a coach in the NBA for 20 years, including interim head coaching stints with Miami and Detroit. He was head coach of the Los Angeles Clippers from 2000 to 2003.
Gentry was the only holdover from D'Antoni's staff in Phoenix. His hiring as assistant coach in 2004 coincided with the arrival of Steve Nash and the subsequent ultra up-tempo offense that propelled the Suns to 54 wins or more for each of the past four seasons.
Porter, who played in the NBA for 17 seasons, went 71-93 (.433) as Milwaukee's coach from 2003-05, leading the Bucks into the playoffs in his first year. He was an assistant with Detroit when he was hired by the Suns, and the intention was for him to bring the Pistons' defense-oriented style with him.
That plan was jettisoned after it became apparent the Suns' personnel were better suited to an up-tempo style.
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