Justin Timberlake isn't the only engaged celeb guy enjoying his last days as a single man.
Jack Osbourne also spent the weekend celebrating his bachelor party with his best buds.
Osbourne left his fiancée, Lisa Stelly, and their 5-month-old daughter, Pearl, in L.A. and hit Las Vegas' Palazzo hotel with a group of guy friends.
On Saturday, Osbourne and his pals hit Azure, where they had a private poolside cabana. "Let the games begin! @PalazzoLasVegas #bachelorparty #palazzo," Osbourne tweeted.
Later that day, the gang headed to Lagasse's Stadium for Oktoberfest, where they watched the UFC fight and dined on traditional Oktoberfest food including bratwurst hotdogs and giant pretzels. "Best bachelor party weekend ever! Thank you @PalazzoLasVegas!" Osbourne tweeted Sunday along with a photo of him and 11 pals enjoying cigars.
Osbourne skipped hitting any nightclubs while in town and instead opted for some early morning hiking trips.
Stelly also took the weekend as an opportunity to celebrate her bachelorette party back home in L.A. "My bachelorette party is better than your bachelor party @MrJackO," she tweeted at her hubby-to-be along with a photo of herself dressed in a white wig, white corset top and white feathered robe.
Osbourne's sister, Kelly Osbourne, also helped Stelly celebrate. "Thanks @MissKellyO for my diamond encrusted riding crop," she tweeted. "I'm obsessed with it, I can't put it down."