By Rick Reeno

During a recent media workout to promote his upcoming fight with WBA champion Amir Khan on May 15, former junior welterweight belt holder Paulie Malignaggi was presented with several questions about the hottest topic in the boxing business - Floyd Mayweather Jr. vs. Manny Pacquiao.

The biggest hurdle in making the fight between Pacquiao and Mayweather is the same hurdle that crippled their negotiations a few months ago. Earlier this year, the negotiations fell apart after the two sides were unable to reach a mutual agreement on the contract clause that called for random Olympic-style drug testing. Both fighters went their separate ways, and won their recent outings impressively, and now the two fighters are back in position to make the richest fight in boxing.

Malignaggi has been one of Pacquiao's biggest critics over the last few months. During the fall of 2009, Malignaggi voiced his suspicions about Pacquiao's possible use of performance enhancing drugs. When Pacquiao and Mayweather broke apart over the issue of drug testing, Malignaggi's voice of concern became a little louder.

In Malignaggi's opinion, Pacquiao is taking some form of a performance enhancer. He also doesn't agree with the recent comments made by trainer Freddie Roach, who suggested Shane Mosley aged in last Saturday's loss to Mayweather.

"Make Mosley and Pacquiao, and watch how much Mosley gets off. He didn't get off because Floyd had an answer to everything he did and not because Mosley got tired. You saw 24/7, Mosley was up in the mountains, he was ducking under towels and doing all of that good stuff. He wasn't tired after two rounds. Everything Mosley did he was getting countered, he was getting smothered, he was getting pushed back, he was getting hit to the body. Floyd was doing everything that he needed to do to take everything away from him," Malignaggi told BoxingScene.com.

"Pacquiao won't do that. Mosley and Pacquiao, that would be a barnburner. Manny Pacquiao don't know how to set you up, he just comes in and throws punches and Shane Mosley doesn't have to worry about being set up, he would come in and throws punches right back. It wasnt about Shane Mosley getting old. It was about Mayweather having all the answers and if they make Pacquiao-Mosley, you will see the difference."

As you can expect, BoxingScene asked Malignaggi for a Mayweather vs. Pacquiao prediction. He places the outcome on the involvement, or preclusion, of a random drug testing protocol. If there is no random drug testing protocol involved, he predicts Pacquiao will go through Mayweather in the same fashion as Oscar De La Hoya, Ricky Hatton and Miguel Cotto.

"I believe Pacquiao is on something. It really comes down to the test. Because I believe Pacquiao is on a lot of good stuff, so if they don't take a test, Pacquiao probably walks through Mayweather because whatever he's on is some strong stuff and he's walking through everybody," Malignaggi said.

But if a random drug testing protocol is involved with the fight, he doesn't see Pacquiao being able to last more than eight rounds. Again, in Malignaggi's opinion, he predicts that a different Pacquaio will show up against Mayweather - if a drug testing protocol is involved.

"You see what kind of a strong welterweight Floyd Mayweather has become. He was pushing back Shane Mosley. He was ripping him to the body. And we know that performance was drug free. Do you know how we know? Because they had the strongest drug testing available in that fight. That performance by Mayweather was 100% pure. You can't take nothing away from him," Malignaggi said.

"If you have that kind of drug testing in fight with Manny Pacquiao, he don't last eight rounds. You won't see the same Manny Pacquiao that you've been seeing. You say 'wow, Manny Pacquiao looks like a killer.' You put him on the drug test and watch him not look like a killer."