MANILA, Philippines – After seeing a different, more cautious Manny Pacquiao cruise to a unanimous decision victory over Jessie Vargas last week, Mexican boxer Juan Manuel Marquez can only come to one conclusion.

Marquez, arguably Pacquiao's greatest rival, said in a Golpe a Golpe interview that even until now, the "Pacman" may still be reeling from his knockout loss against "Dinamita" back in 2012.

In the fourth fight of their remarkable saga, Marquez finally claimed the decisive victory he so longed for when he knocked out Pacquiao with just one second to go in the sixth round. The punch that sent Pacquiao face-first to the canvas was a short counter-right hand, incidentally the same kind of punch that Vargas has learned to master.

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"Those right hand blows that landed from Jessie Vargas made Manny Pacquiao think," Marquez said, as quoted by Boxing Scene. "Getting hit with that right hand counter is still fresh in his memory."

It was still Pacquiao who dealt the more telling blows in his bout against Vargas, and even floored the young fighter in the second round. But Marquez noticed that the Filipino star was "more cautious, more thoughtful in his attacks" – likely to avoid getting caught with a counter.

"He no longer throws punches thoroughly," Marquez observed. "So he looks more cautious, fights more from a distance, and he's not looking like he did in the past, when he fought with that speed, with his animosity to knock the opponent out."

"Today, we see a more cautious fighter, and he's not winning fights like he used to," he added.

What made Pacquiao's cautiousness more noticeable is that he was up against a fighter not known for his punching power. Marquez pointed out that Vargas went into the bout with only 10 knockout victories, and yet the "Pacman" still hesitated whenever he got hit.

"We saw him get hit by a fighter who doesn't have a strong punch," said Marquez. "Jessie Vargas… doesn't have a strong punch, yet he staggered (Pacquiao)."

Pacquiao has not won by knockout since his 12th round stoppage of Miguel Cotto in 2009.

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