Freddie Roach doesn't believe Jeff Horn will be blinded by the bright lights when he embarks on the biggest challenge of his career, by far, against Manny Pacquiao for the WBO welterweight crown at Suncorp Stadium.

Pacquiao's blinding speed in the ring could be another story. While Horn and his camp believe they have found the keys to derailing Pacquiao through a secretive 10-point plan, Roach doubts any strategy they come up with will be able to combat the Filipino's brilliant hands, which have dazzled some of the best in the business.

While Horn has age on his side – at 29 he's nine years younger than Pacquiao – the fight represents an immense leap in class for the Brisbane challenger, who has quit his former life as a school teacher for what can only be described as a dream opportunity against an all-time great.

Roach, who has guided Pacquiao for the majority of his career, said Horn would notice that the most through Pacquiao's hand speed. The legendary trainer was overwhelmingly respectful towards Horn but remains supremely confident Pacquiao will produce a vintage performance in the centre of the famous rugby league ground.

"Manny's speed is unbelievable. You don't really know his speed until you go in there against it. It's a big step [for Horn] but he has the opportunity of a lifetime ... it's a great moment in his life and I hope he takes advantage of it. But I don't think he will," Roach said.

"Not in this fight. I'm very confident in my fighter and I'm very happy with the second half of this camp. He's dancing a little bit, singing a little bit. He's having fun.

"Speed is his gift. If I could pick something in boxing, that would be the No.1 gift I would like. Speed will be overwhelming, I feel."

Roach believes Horn has little choice but to press the issue from the opening rounds. He has prepared Manny accordingly, while Pacquiao would later say he welcomed an early challenge from his opponent, who will have a clear weight and size advantage.

And, despite early concerns about Pacquiao showing signs of lethargy in training, Roach now rates this camp as one of the most-polished in recent memory for his stable star, who splits his time between boxing and duties in the Filipino Senate.

If they needed any added help, Roach even has a fighter under his tutelage who fought and beat Horn as an amateur. Every insight helps at this level and Roach could hardly believe his luck when 22-year-old Eimantas Stanionis piped up at the Wild Card gym.

"I first heard of Jeff Horn when we were offered the fight. I hadn't heard of him before that, no," Roach admitted.

"But I have studied a lot of tapes on him, as far back as I can get, and I do have a Lithuanian fighter who beat Horn as an amateur.

"We've had a lot of discussions on how he beat him and so forth. I was talking about Manny's fight coming up and he said 'I fought him in the amateurs'. He's had 400 amateur fights so he's probably fought everybody. We talked a little bit about styles but I'm sure a lot has changed since then."

Roach doubted whether Horn's main sparring partner, Filipino Czar Amonsot, offered a great deal when compared with Pacquiao, although the Horn camp feel they came out of their sessions with the required work under the belt.

"I know that fighter [Amonsot]. He's been in my gym before, sparred with one of the guys. Is he a good clone of Manny Pacquiao? I don't think so. Not even close. I guess that got as close as they could."

Roach was happy to spruik a potential rematch with Floyd Mayweather but that depended heavily on not just the result on Sunday but the manner of any victory, or defeat. A poor showing, he said, would see him recommend Pacquiao hang up the gloves.

"He's had quiet a few fights. We're getting close to the end, I know. I think he maybe has a couple more fights in him after this one. But if he struggles in this fight, it could be over," Roach said.

"Depending on how he lost but I would probably encourage him to retire."