One person you won't hear complaining about the Sixers' 114-112 loss to the Boston Celtics is Angelo Cataldi. Not because he doesn't have an opinion — because he's not on the air.

For the second-straight morning, SportsRadio 94.1 WIP's outspoken morning show host was off the air after having left mid-show Tuesday with a severe kidney-stone attack. Cataldi said on Twitter Wednesday night that he was scheduled to undergo surgery Thursday to have kidney stones removed.

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"I'll keep you posted. Thanks for all the words of support," Cataldi wrote.

This is the second time in recent months Cataldi has been forced off the air due to health issues. In November, the 67-year-old host missed about a week and a half after an emergency gallbladder surgery left him hospitalized.

"I've had the 10 worst days of my life," Cataldi said following the surgery, calling in to his WIP show. "What they said to me was when they took it out, it has gangrenous cells in it. It was really, really awful. They couldn't believe I didn't have any symptoms."

This time, the situation appears less serious, and barring any unforeseen complications, sources at the station expect Cataldi to return by next week. Filling in will be Marc Farzetta, who recently took over as the daily host of NBC Sports Philadelphia's Philly Sports Talk alongside NBC Sports Philadelphia anchor and reporter Amy Fadool.

Don't expect Cataldi to get much sympathy from his colleagues. Last time around, co-host Al Morganti put Cataldi's gallbladder on the station's prize wheel, and comedian Joe Conklin mocked his hospital stay by voicing a series of visitors, including former Eagles head coach Chip Kelly.

"I'll never forget all the support you gave me while running the Eagles," Conklin said in the voice of Kelly. "I never could have stolen all the money from Jeffrey [Lurie] without your help."

In December, Cataldi renewed his contract with WIP, which will keep him around at least through the end of the year. After nearly 30 years, he still remains WIP's most marketable star and a ratings giant, easily beating 97.5 The Fanatic's Anthony Gargano and former Daily News reporter Bob Cooney in the latest quarterly ratings book.