Right that's all from me, thanks for your company and congratulations Amir on a stunning performance.
"Boxing far too easy for Khan, Judah looking for an excuse, it was on the belt so not low. Craig in Birkenhead on 81111.
Television replays of whether Khan's knockout punch was low are inconclusive. He strikes Judah on the waistband which was pulled up rather high. Nonetheless the right beforehand rocked Judah who seemed to be looking for a way out.
So what now for Khan? Still time for you to text in via 81111. Khan's manager Asif reveals Amir will next be action in December but doubts whether it will be WBC champion Timothy Bradley he faces.
"The future of boxing is in safe hands, he is a star of the future," says WBC light-heavyweight champion Bernard Hopkins.
"Tonight was the biggest victory in Amir's career. We really don't need to fight Timothy Bradley, he needs us more than we need him. Amir is the king of the division. I really don't think Bradley wants anything to do with Amir after the performance. He has moved onto a new level," says Richard Schaefer - CEO of Golden Boy Promotions.
"I was headbutted in the first round and it was a low blow in the fifth. I thought he was giving me time to get up. I didn't understand the finish," says Zab Judah.
More from Amir Khan
on the prospect of fighting Timothy Bradley: "I think Timothy Bradley is scared of me. I am ready to fight him."
0350: Amir Khan
- "I felt great in there, he caught me with a few shots but they didn't hurt. I don't really feel like I've been in a fight. Zab's a great fighter and he has been a great champion. It wasn't a low blow, it was a good punch."
Stunning performance from Khan, he won every round and the finish was lethal. A right to the body knocked the wind out of Judah.
0345: Britain's Amir Khan wins by fifth-round knockout
Khan holds the centre of the ring and is picking off his opponent at ease. There is another clash of heads, but it is only minor, and two jabs from Khan bloody Judah's face further. Khan is looking electric in there and a right-hand to the head and a right to the body floors Judah. It looks low but Judah doesn't get up. It's all over.
A left-right, left-right combination from Khan finds the target and halts Judah's momentum at the start of the round. Judah's nose is bloodied now as Khan stalks him around the ring. Judah's footwork at the moment is lively but there is very little coming in the way of punches from the New Yorker. Khan is happy to box at range and ends the round with another left-right combination. It's all Khan.
Judah starts the round brightly but Khan's pace is relentless as he continues to beat his opponent to the punch. Judah's right eye is swollen but he tags Khan with a fierce jab. Khan ends the rounds on the front foot and a looping left hurts Judah. This is a fine performance from Khan.
Khan finds success early in the round with two jabs but his opponent is hard to catch. The Bolton fighter is the aggressor throughout though and pins his opponent against the ropes late in the round and peppers the body before a late one-two on the bell from Khan sees him end the second as he started it - on top.
Khan starts on the front foot and makes a bright start, a one-two from the Bolton fighter falls just short, but he's going after Judah. Two jabs find the target from Khan as he shows electric hand speed and also lands a right to the chin of Judah. A right hook from Judah rocks Khan before a clash of heads between the pair. Judah is already heavily marked around the right eye from that clash. Great round from Khan.
The pair are introduced by Michael Buffer as he goes through the pre-fight necessities before his trademark "Let's get ready to rumble" roars out around the Mandalay Bay resort and casino. We are nearly ready for the first bell. Judah looks super composed, Khan is edgy.
Khan is next to make his way into the ring. There is a healthy contingent of British fans in Vegas but it must be said that Khan looks nervous as he makes his way into the ring.
Remember BBC Radio 5 live commentary is available now. Follow the link at the top right of this page/
They are not messing around in Vegas with Zab Judah the first to make his way into the ring bang on schedule. He looks calms and composed and in excellent shape.
"Hard to pick this one. I feel Judah is passed his best, but is still VERY dangerous. Khan should have too much for him, as he has moved on so much in the last 18 months. I'll say Khan win by KO in round 7." Matt
(suffering from toddler induced insomnia) via text in Sheffield
"Morning Nabil. Here's hoping that Amir can do the business against what surely is his biggest challenge so far. I'm pretty confident he can, but even if he does I really can't see him standing a chance against Mayweather." Alex via text on 81111.
Not long to go now before the main event with Khan v Judah the next fight on at Mandalay Bay resort and casino. Khan
, 24, has won 25 of his 26 fights with that one defeat coming against Breidis Prescott in 2008. He has 17 stoppages to his name. SouthpawJudah
, 33, is far more experienced with 49 fights under his belt. He has 41 victories and 21 knockouts to his name.
You can also get involved by texting in via 81111
by putting BOXING
before your message. I want your fight predictions and your chat.
As well as following our live text commentary you can listen to the fight on BBC Radio 5 Live where Ronald McIintosh will be taking you through proceedings in Vegas. Just follow the link on the top right hand corner of this page.
Good evening/good morning, boxing fans of the world wherever you are welcome to the live text commentary of Amir Khan's fifth defence of his light-welterweight belt. I'm Nabil Hassan and I'll be taking you through the action in Las Vegas as Khan looks to add Zab Judah's IBF belt to his WBA title.