On 31 May 2011, Khan agreed to fight 33-year-old two-weight champion Zab Judah (41–6, 28 KOs) in attempt to unify the WBA, and IBF light-welterweight titles in Las Vegas on 23 July. Judah had reclaimed the IBF title two months earlier against Kaizer Mabuza. Khan was unhappy that a fight with Bradley could not be made. He said, "Bradley was the guy I wanted to fight but he chickened out. I offered him 50% of UK revenue, which is unheard of, and 50% of all revenue in America, that's how much I wanted to fight him, but he didn't want it." The fight was broadcast on Primetime in UK and HBO in the US. Round one saw a busy Khan as he fought from the outside and kept Judah away with jabs and straights. All four rounds were taken by Khan. Ultimately in the fifth round Judah was taken down with a right uppercut to the body, in which at first commentators believed it was a low blow, since Judah was showing signs of agonising pain, but when it was seen from a different camera angle, it was right on the belt, leading to an 18th knockout (KO) for Khan in his career so far. Khan later rejected claims for the low blow saying, "He went down. It was above the belt. Zab's a great fighter. I respect him a lot. But it was nowhere near below belt. It was a great shot." Over five rounds, Khan landed 61 of 284 total punches (21%) and Judah landed 20 of 115 (17%). For the fight, Khan earned $1,072,500 and Judah had a $500,000 purse. The fight averaged 1.4million viewers on HBO, peaking at 1.417million viewers.