On February 25, 2006, in a stay-busy fight, Brock faced Zuri Lawrence on the undercard of the fight between Shane Mosley and Fernando Vargas on HBO PPV at the Mandalay Bay Events Center in Las Vegas. Regarded by the public as an experienced journeyman with a record of 20 wins, 10 losses and 4 draws, Lawrence was coming off of upset victory over Jameel McCline. The first five rounds were tentative, with Brock slowly breaking Lawrence down and winning every round. At the end of the sixth round, Brock caught Lawrence with a left hook, knocking him out cold. Lawrence fell flat on his back and was unconscious for several minutes. Brock remains the only boxer to knock Lawrence out. The knockout received "The Ring"'s KO of the Year award. At the conclusion of 2005, Brock was ranked No.7 heavyweight in the world by "The Ring" and No.9 heavyweight by BoxRec.