Credit: Steven Lawton/FilmMagic

Is your temperature rising? 

Former 98 Degrees frontman Jeff Timmons is back onstage -- this time at the Rio Hotel in Las Vegas as a part of the Chippendales show!

The 38-year-old told TMZ last month he would take off his shirt for the act, but nothing more. "[The Chippendale regulars] don't even strip… they're like trained dancers," he said. "The days of your grandma sticking dollar bills in a stripper's G-string are over."

But to the delight of the screaming audience, Timmons ripped off his fitted white T-shirt and tossed it into the crowd during his debut on May 12. He then continued to sing for the roaring crowd, flaunting his chiseled abs and pumped-up pecks.

Timmons will continue his stint as the Chippendales' musical act through June 5.