European lightweight champion John Murray says that challenger Karim El Ouzaghari's left hook will be the danger weapon this Saturday.
Manchester star Murray (30-0 18KOs) makes his big return to London for the first time in over four years to headline at Bethnal Green's York Hall with the second defence of his title.
The former British champion hasn't seen much of the tough Spaniard (11-1-2 4KOs), but the few clips he has seen of him have him concerned.
"The fighters that you can't find any footage of are the ones you need to worry about and the little that we did find made him out to be a devastating puncher - especially with the left hook," said Murray.
"There is one fight where he flattens the guy with it and me and my trainer Joe Gallagher just looked at each other.
"We've been working on stuff in the gym to counter it and we're confident that it won't cause us a problem, but you never know when you get in that ring and the bell goes.
"I've trained harder than ever for this fight and I'm not taking anything for granted with this guy. He's going to up my game and you'll see the best of John Murray."
Murray, 26, is expecting a big reception in the capital for his first fight under new promoter Frank Warren and the show is being billed as "Here's Johnny" from the horror movie The Shining starring Jack Nicholson.
Ranked number two by the WBC and six by Ring Magazine, Murray is looking to put on a devastating performance ahead of a potential world title shot later this year.
He added, "A lot is riding on this fight and I need to put on a top performance to keep the world title shot in line.
"I'm live on Sky Sports and the York Hall will be packed out so I'm determined to give the fans what they want and that's action with a knockout ending."
