US great Michael Phelps bowed out of Olympic competition in golden style Saturday as Britain’s Jessica Ennis provided theLondon Games’ signature moment with a dazzling heptathlon win.

As Usain Bolt and Yohan Blake made their first appearance on the track, Phelps made sure of his 18th Olympic title — and 22nd medal overall — in the 4x100m medley relay, the climax to races in the Aquatics Centre pool.

But the night’s biggest roars were reserved for Ennis, who confirmed heptathlon gold with a surging 800m win that had the 80,000-capacity Olympic Stadium crowd on its feet in a spine-tingling ovation.

“Awe-inspiring win for Jessica Ennis,” tweeted Prime Minister David Cameron.