On Thursday, just days after Britney Spears left Las Vegas, her two exes, Justin Timberlake and Kevin Federline, arrived in Sin City though for different reasons. Timberlake, who is performing Friday night at the MGM Grand, came to town with best friend Trace Ayala. He began his visit at the Mirage, playing blackjack in the high-rollers lounge for an hour, before heading to the Hard Rock Hotel's Nobu for a sushi dinner with a small group of friends. Dressed in a black bomber jacket and jeans, he looked "very mellow and cool," said one observer at the restaurant. He "gave off a casual and comfortable vibe." After dinner, Timberlake hung out at the MGM Grand Mansion, an ultra-exclusive hotel modeled after an 18th century Tuscan villa and reserved for celebrities and Vegas's high rollers. Meanwhile, Federline, in town to check out the World Extreme Cagefighting matches at the Hard Rock on Saturday, played the slot machines at the Venetian with friends before hitting the Tao nightclub, where go-go dancers entertained the crowd beneath sprinkles of artificial snow. Federline, who filmed his Nationwide Super Bowl ad earlier in the week, also seemed to be in a mellow mood, spending time in the VIP section at a table next to some of Timberlake's dinner companions. He and his crew kept mostly to themselves, had Grey Goose vodka stocked on the table and enjoyed the sounds of DJ Five until 3 a.m. "He wasn't drinking much and really only talked to a couple of his friends," said one clubgoer. "It seems like he's trying to move on from past Vegas visits where it was all about the bling bling."