By Nigel Hunt

LONDON (Reuters) - Brazil's Emanuel Rego and Alison Cerutti were grateful to see familiar faces on Tuesday as the gold medal favorites bounced back from a wobbly start to the Olympic men's beach volleyball tournament and cruised into the knockout phase.

The Brazilians hit top form as they comfortably defeated Patrick Heuscher and Jefferson Bellaguarda of Switzerland 2-0 (21-17, 21-12) at a cold and cloudy Horse Guards Parade in London.

"If they play like they played today, they can beat every team, but in their first match they didn't play very well," Heuscher told reporters.

Beijing gold medalist Emanuel said the key difference was playing familiar opposition.

The Brazilians narrowly averted one of the biggest upsets in Olympic beach volleyball history in their first match when they faced a recently formed Austrian pairing of Clemens Doppler and Alexander Horst, the bottom ranked team in the tournament.

"I think the big difference (was) we didn't know the team, we have never played them. It was hard to find a good strategy and they showed they knew everything about us," Emanuel told reporters.

It was the third time they had faced the Swiss.

"We knew their best points and worst points and we tried to create a good strategy and that I think was the difference between the two matches," he said.

Emanuel was also happy it wasn't raining.

"Today when I woke it was raining and cold and I said it would be a tough day for playing beach volleyball, but as soon as we get here, the sun has a little bit come out but it is still cold," he said.

"If you have sun it is best for everyone. Beach volleyball is just a party. More sun, more enjoyment for everyone."

In the other early match, the blocking of Premysl Kubala helped the Czech Republic secure a first tournament win as his teammate Petr Benes battled flu.

The Czechs defeated Japan's Kentaro Asahi and Katsuhiro Shiratori 2-1 (17-21, 21-12, 15-7).

"I'm going to bed as I'm cold and sick. I'll stay in bed for two days and get up on Thursday for the (next) match," Benes said.

(Reporting by Nigel Hunt; editing by Jason Neely)