By Phil Barnett

As tiresome speculation drags on over whether Manny Pacquiao will finally collide with fellow superstar Floyd Mayweather, the boxing world runs the risk of overlooking the last man to truly test the Filipino firebrand.

Juan Manuel Marquez, the most enduring but under-appreciated of Mexico's recent generation of greats, gave current pound-for-pound king Pacquiao all he could handle in their two previous meetings.

The results did not go his way - he was floored three times in the first round in 2004 but still claimed a draw, then lost a split decision in 2008 - yet the Mexico City veteran not only disputes those results, he can also lay claim to playing a fundamental part in the legacy of a legend.

Back in 2004, Pacquiao was merely one of several hugely talented and exciting small guys stealing the limelight from the flagging heavier weights.

Yet the Filipino's battles with Marquez were even more influential than his memorable scraps with two more marketable Mexicans, Marco Antonio Barrera and Erik Morales, in his path to pound-for-pound greatness.

As talk of a showdown between Pacquiao and Mayweather re-ignites, the part-time politician would do well to keep his eyes firmly locked on his 38-year-old rival this weekend.

"I will never underestimate Marquez," vowed the 32-year-old Sarangani Province Congressman.

"I trained hard for this fight and feel strong. This is a lot different because over the past few years I have improved a lot.

"I think I am a lot better now mostly because of my right hand. There is also a big difference in my power and moving up in weight from our last fights is going to be a difference. I move better now too.

"I know Marquez's style very well from the first two fights so that's where we will start again. We have started different moves for his counter-punches so I'm ready for this fight."

Notoriously nice guy Pacquiao supposedly has extra fire in his belly after Marquez recently implied he was undone by the judges in their first two encounters.

"That's why we are doing this third fight," said Marquez.

"The first two were very close and this fight should end all doubt. We are not the only ones saying we won the fights, there are a lot of fans and media out there saying the same thing - that we won those two fights.

"If he is upset about what I said about winning the first two fights...well, I'm upset that I didn't get the decision. I'm motivated just as much as he is.

"We all have opinions and my opinion is that I didn't get the decisions I deserved."

While Pacquiao has been riled by Marquez's belated complaints, the Mexican insists he is the man with a score to settle.

"Without a doubt the fight is personal for me too," he admitted.

"I didn't get the two decisions I thought I won.

"I think I will win this fight because I should have won the first two. It is going to be great because we both want this fight and we are going to give it our all.

"The winners are going to be the fans because we are two guys that are going to go in there and give it our all."

All the signs point to this third instalment being the least competitive chapter of an otherwise thrilling trilogy. Only if fortune really does favour the brave will it be third time lucky for perennial bridesmaid Marquez.

Phil Barnett covers boxing for Press Association Sport