Great Britain booked their place in the Olympic quarter-finals with a routine victory over Cameroon at the Millennium Stadium.

Captain Casey Stoney set them on their way with a close-range finish in the 18th-minute, with Jill Scott adding the second five minutes later.

Steph Houghton, the heroine of the opening win over New Zealand, sealed the win with her fierce strike eight minutes from time.

And with Brazil and GB having recorded two wins from two, both sides are guaranteed a last-eight berth ahead of their meeting at Wembley on Tuesday.

There were moments of concern for coach Hope Powell thanks to some robust tackling from their African opponents, although it was an innocuous challenge from Ajara Nchout that saw defender Ifeoma Dieke leave the field on a stretcher during the second half.

Powell admitted her side had been affected by nerves when opening the sporting action at these Games against New Zealand on Wednesday.

But there was no sign of anxiety on this occasion with GB producing several bright passing moves during the opening exchanges.

The most promising of those attacks saw Kelly Smith, Anita Asante and Eniola Aluko link well, only for the winger to miscontrol at the crucial moment.

Britain's dominance got its reward in the 18th minute, captain Stoney was left with the simple task of tapping in from close range after Cameroon keeper Annette Ngo Ndom got nowhere near Karen Carney's free-kick.

The lead soon doubled thanks to some excellent build-up involving Smith and Kim Little, with the Scotland international's lovely backheel allowing Scott all the time she needed to pick her spot.

Ngo Ndom made some amends for her error for the opener by denying Smith after an incisive pass from Scott had split the Cameroon defence.

Some of Cameroon's challenges had been agricultural to say the least and substitute Bibi Medoua was fortunate not to see red for a crude, late and high lunge on Alex Scott.

Chances were coming thick and fast for the home side, Ngo Ndom did well to save from Little, before palming a header onto the post from Houghton.

Cameroon were in disarray and several of their players were involved in a heated debate at the half-time whistle, before calm was restored and the team shared a huddle before departing for the sanctuary of the dressing room.

Whatever was said made little difference however, as GB remained firmly in control.

Asante had a header cleared off the line by Medoua, while Houghton's fierce drive was tipped wide.

But Powell's side were dealt a blow when Dieke was stretchered off after she went down holding her knee following a battle for possession with Nchout.

Little was again denied by the Cameroon keeper after Carney's raking pass had picked out Aluko racing down the right.

But the third goal eventually arrived as the impressive Little fed Houghton for the full-back to send a rasping drive into the back of the net.