MANILA, Philippines — Nonito Donaire was a mere shadow of his old, championship-level self losing in Las Vegas this past weekend.

Complacency could be one of the culprits, Manny Pacquiao said.

Pacquiao was uncharacteristically blunt in assessing his countryman's performance, one that saw Donaire lose his world super-bantamweight belt to American Jessie Magdaleno.

"In boxing, you can't lose your focus during training," Pacquiao said in an interview with Manila Times. "You need to train well. That's boxing. You can't fool around during training."

Pacquiao, who came away with a win in his own world title fight in the same card, knows a thing or two about the importance of staying locked in. In Pacquiao's younger days, trainer Freddie Roach used to call him out for distractions that dogged their pre-fight preparations.

Attending to his duties as a senator and getting ready for a prizefight has taken some toll on Pacquiao but he's proven to be such a unique athlete who can easily shift his focus from one task to another and give each the required attention to succeed.

Critics said Donaire's loss could be attributed to a change of trainers and consequently a change in practice regimens. Pacquiao said that shouldn't be an excuse.

"It doesn't matter what the quality of your trainer is. If you don't work hard, nothing will happen," Pacquiao said.

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