Amir Khan claims he has improved so much in the last two years his sparring sessions with the great Manny Pacquiao are "pretty even" - but insists he will never fight his friend for real.
The British fighter relocated to America to train under renowned coach Freddie Roach in 2008 after suffering a stunning first-round defeat by unfancied Colombian Breidis Prescott.
Since then, the 2004 Olympic silver medalist has produced a five-fight unbeaten run which has seen him overcome that setback to claim the WBA version of the light-welterweight titles.
Much of the credit must go to Los Angeles-based Roach, but equally crucial has been the presence of pound-for-pound king Pacquiao under the same roof at the Wild Card Gym.
Even two years ago the pair's sparring sessions were reportedly explosive and now, although the pair have become good friends, their clashes are something to behold.
Khan, who defends his title against mandatory challenger Marcos Maidana in Las Vegas on Saturday, told Press Association Sport: "There's definitely a massive difference and I can see it myself.
"It's just amazing to have Manny in the same ring and to share the ring with him. It's an honour because he's the pound-for-pound best fighter in the world and I think it's a great thing, you can't buy that.
"It's something that I've been very lucky to get because I'm in the same camp.
"Sparring is very even. Some days he gets the better of me, some days I get the better of him. But it's mostly even. You've got two fighters in there who are very hungry, with big hearts, who are both quick and powerful, so really it's amazing how we both spar because we're both technical as well.
"It's a good spar because I learn so much off Manny as well. But it's pretty even."
The 24-year-old added: "Sparring with Manny, he's hitting me with his
best shots and I've not gone down in sparring, ever."
Roach has previously suggested he could make a fortune selling tickets
to watch the two firebrands go at it in the gym - but Khan insists they will never go toe-to-toe without headguards and big gloves.
He said: "I wouldn't want to fight Manny because I think it puts me in a bad position, especially as I train with Freddie Roach and I don't want to put him in that position of having to pick between us. The same goes for our conditioning coach, Alex Ariza. I don't want to put him in that position.
"So, really, I would never fight Manny because it would cause too many complications. On top of that, Manny and I are good friends. We eat at the same restaurants, we travel in the same car, we run and train together every day, we've built that bond up.
"We're really good friends and I think it would be tough to fight him."
Khan admits the pair have exchanged banter about the idea of them fighting for real.
"We're always having a laugh but I think Manny's made it clear he's going to call it a day in the next couple of fights because he wants me to take his place in the Wild Card Gym and make a name for myself.
"He's saying he's had a great career - over 50 fights - and he's going to have his last few big fights and call it a day, probably.
"He's very gutted that the Floyd Mayweather fight has not come off. I think it's a fight he could do really well in.
"He's gutted, when we speak about it he says he's going to leave it to his promoter, Top Rank, and that he'd fight anyone, he pushes for the fight but it's not happening.
"He doesn't get frustrated, he's never let it get to him because he's always been active, fighting other people.
"He's pound-for-pound king, so what he's got to prove?"