In his pro debut on September 15, 2000, Jimenez challenged Artur Petrosyan in Petroysan's Las Vegas, Nevada backyard.

On February 2, 2002, Jimenez stunned ringside observers with his three-round demolition of fellow undefeated jr. lightweight Jadschi Green (TKO 3).

Green, who entered the bout with a record of 4-0-2, 4 KO's, attempted to utilize his five-inch reach advantage to box and frustrate Jimenez.

Jimenez bloodied Longakit's nose and swelled both his eyes with stinging overhand rights to dominate the bout from the opening bell.

On August 2, 2002, Jimenez stopped Marty Robbins in the first round with a crippling left hook to the body (TKO 1).

Just weeks later on August 30, 2002, Jimenez won a technical decision over Nelson Medina after suffering a cut from an accidental head butt in round two (TD 4).