England won by six wickets after a Pakistan batting collapse featuring three run-outs in Sharjah on Tuesday.
The Daily Mail reported that the match was the subject of an investigation into suspicious betting patterns.
"There was nothing wrong with that game. I have no doubts about my boys," said former bowler Waqar.
The ICC declined to confirm or deny that it was investigating the game.
Pakistan collapsed from 132-2 to 208 all out before England triumphed with nine overs to spare.
Waqar said: "Yes, we lost the game. You lose and win games, and it's unfortunate the way the whole thing happened."
ICC chief executive David Richardson told BBC Test Match Special: "I wouldn't be suspicious of that game."
He said Pakistan had reported approaches from bookmakers in recent times.
Pakistan coach Waqar Younis has dismissed suspicions over his side's performance in the third one-day international against England.