Bayern Munich coach Hansi Flick trusts his side to forget their demolition of Barcelona and "start from scratch" when they face French giant-killers Lyon in Wednesday's Champions League semi-final.

Bayern marked themselves as favourites to lift the trophy by hammering Barcelona 8-2 in their quarter-final last Friday when Thomas Mueller and Philippe Coutinho both scored twice.

The shockwaves are still being felt in Barcelona where both coach Quique Setien and sports director Eric Abidal have been sacked.

Following that jaw-dropping victory, Bayern are "really hungry" for more success, says captain Manuel Neuer.

However, semi-final opponents Lyon have punched above their weight by beating Juventus and Manchester City to reach the last four.

Flick takes confidence from the "very good atmosphere" and "enormous quality in training".

"That gives you confidence in the team. I'm relaxed because, I know that they're very focused and have big goals."

The Bayern boss warns "the game starts from scratch. We have to play like we did against Barcelona. Less than 100 percent will not be enough".

His side have won their last 20 matches in all competitions, securing an eighth straight Bundesliga title and lifting the German Cup in the process.

Their striker Robert Lewandowski is the Champions League's top-scorer this season on 14 goals -- three short of Cristiano Ronaldo's record.

Bayern winger Serge Gnabry, who has seven so far in the competition, including four in the 7-2 thrashing of Tottenham away in the group stages, says they must not underestimate Lyon.

"I think we were all surprised by the end result (against Barcelona), but Lyon will be a different opponent in a different game," said Gnabry

"They've beaten Juventus and Manchester City - both those teams were favourites. It looks like we're favourites now and we have to be careful."

Flick knows what to expect from Lyon coach Rudi Garcia.

"They are very compact in defence, can run all day and are strong on the counter-attack," he said.

"We want to reach the final and beat Lyon, knowing full well that it's not that easy, so we have to be on the front foot from the first minute."