LAS VEGAS – "The Ultimate Fighter 11" veteran Jamie Yager and K-1 kickboxing vet Kultar Gill were among approximately 150 welterweights who attended Monday's open tryout session for "The Ultimate Fighter 15."

Additionally, more than 200 lightweight fighters also attended the all-day session, which aims to secure a cast for the upcoming edition of the reality series, set to begin filming in early 2012.

The prospective cast members gathered at the Fertitta family-owned Texas Station Hotel & Gambling Hall in Las Vegas.

UFC president Dana White and UFC matchmakers Joe Silva and Sean Shelby were among the executives judging the hopefuls through grappling matches, striking workouts and interviews. FX Director of Production Maureen Timpa also attended the tryouts.

Gill, who has not competed in a professional MMA contest since 2008, was a perhaps-surprising entrant into the 170-pound field's very first group of applicants. But it was "The Black Mamba" and fellow hopeful Cortez Coleman whose grappling match brought the first cheers from the crowded room after a few safety-first matches kicked off the festivities.

A DREAM and K-1 Hero's veteran, Gill boasts MMA fights with Yves Edwards, Joachim Hansen, Tatsuya Kawajiri and Caol Uno, among others.

Meanwhile, Yager made it to the quarterfinals of "The Ultimate Fighter 11," downing Charlie Blanchard and Ben Stark while competing as a middleweight. He was ousted from the tournament by Josh Bryan and then released from the promotion after suffering a second-round TKO loss to Rich Attonito.

Yager has since dropped to 170 pounds and rattled off three-straight stoppage victories.

Other notable welterweights included MMA veterans Sam Alvey, Blas Avena, Rudy Bears, Zak Cummings, Jacob McClintock, Leopoldo Serao and Dave Terrel, as well as a host of young prospects who each had to confirm a winning record with promotion officials before entering the actual tryouts.

Several fighters attended the session to advise their pupils, cheer on their teammates and simply watch the proceedings. Joe Lauzon, Vinny Magalhaes, Cody McKenzie, Brad Tavares and others were on hand for a stint, and MMA superstars Vitor Belfort and Wanderlei Silva also made cameo appearances during the day.

At publication time, the 200-plus lightweight fighters were just beginning their session, and FX officials declined to divulge the roster of participants.

"TUF," which debuted on Spike TV in 2005 and quickly became a driving force for the UFC's move into the mainstream, had launched the careers of more than 100 UFC fighters and has produced past champions such as Rashad Evans, Forrest Griffin and Matt Serra. The 14th season, which concluded this past weekend, was the first to feature bantamweight and featherweight fighters.

"The Ultimate Fighter 15" marks the first edition of the long-running program to air on FX. Unlike past editions of the series, "TUF 15" sees each week's elimination fights air live.

Current plans call for "TUF 15" to air over a 12-week span. Coaches for the show have yet to be determined, and it's still undetermined if the show's contestants will be kept in seclusion for the entirety of the show. Past editions of the series featured fighters living in a house together without television, phones and the like. The arrangement was necessary due to the tape-delayed nature of the broadcasts.

White, Silva and Shelby will travel to Sao Paulo, Brazil, later this month for a Dec. 14 tryout for the first-ever Brazilian version of "The Ultimate Fighter." According to sources close to the promotion, nearly 500 fighters have already registered for the session.