McGinty admits the defeat to the French side has only hardened the team to succeed and produce a performance in Madrid.
"We were all obviously disappointed from the game on Thursday, we had a game plan and we didn't particularly follow it very well, plus the injuries didn't help us," said McGinty.
"I think everyone is now looking forward to the Madrid game. We've got a lot of admiration for the teams in Spain and it's a good opportunity for us to go out there and play against a team that we don't really know too much about.
"Crucially, it is a must win and we enjoy playing in the Amlin Challenge Cup. It's something we want to win as it's another way to the Heineken cup and everyone's looking forward to this week and we believe we're going to win."
With Harlequins now just over a week away in the Guinness Premiership plus mounting injury worries, McGinty admits Warriors will look to rotate players and freshen up the team.
He said: "We've looked at our squad and the guys who've played a lot of game time - they're the ones we need to rest more than anyone else. We will put out a strong team, one that is going to win.
"It will be good for players like Jake Abbott, Matt Cox and James Collins to play in a different part of the world, good to see if they can take an opportunity to put some pressure on the guys around them.
"We enjoy this competition. It refreshes people to play in Europe, getting to travel to different countries.
"The food is different, the climate is different and it freshens up the squad up, all of them are hoping they are going to go to Madrid. It's nice to play against the French teams or the Spanish teams - it spices it up a bit and helps the competition for places."