Amir Khan will take special interest in Saturday's world lightweight championship showdown in Las Vegas between Manny Pacquiao and David Diaz.

But any hopes the ambitious Khan entertained of fighting the winner were dashed by the manner in which he retained his Commonwealth title and extended an unbeaten record to 18 fights against Michael Gomez.

Khan was forced to climb from the canvas in the second round in Birmingham before battering the gritty Gomez to a stop in the fifth.

But while his trademark speed and power were evident, it was clear the 21-year-old is not yet ready to share a ring with the likes of Pacquiao, the fearsome three-weight champion from the Philippines.

Promoter Frank Warren said: "Amir needs more schooling. When he challenges for a world title we want him to win it and defend, and that will take time."

Khan conceded his performance against Gomez could have been better, admitting: "Sometimes I do fight with my heart rather than my head.

"I made a couple of mistakes but I will learn from them."