Skipper Steph Houghton says the key to Manchester City Women maintaining their 100 per cent start to the 2019-20 season is keeping clean sheets.
City have edged above of Arsenal at the top of Women's Super League, ahead of the two clubs' Champions League last-16 ties on Wednesday.
And England defender Houghton is proud of City's defensive efforts, in not having conceded a league goal so far.
"We're in a good place. We couldn't ask for a better start," she said.
"To have had the clean sheets and wins we've had, we should be very proud of ourselves. But we still feel we have a lot more to give.
"We pride ourselves on making sure there's a zero against the opponents' name. That's the basis of who we are as a team.
"We have very good attacking players but ultimately, for us defenders and the way we're structured, we have to make sure we keep as many clean sheets as we can."
"I don't think it's a case of getting revenge against Atletico," said Houghton, ahead of the first leg at the Academy Stadium.
"It's more for us as a team - we want to progress our season. But we know that our performance over the two legs against Atletico last season was not good enough.
"We fully respect them - they're a very good team - and we have to make sure that come Wednesday, we're defensively organised and that when chances come, we take them."
To add to the sub-plot, Houghton will this time be up against her England team-mate Toni Duggan.
This will be Duggan's first meeting with her former club since leaving City in 2017 for Barcelona, where she spent two years, winning a Champions League runners-up medal last season, before moving to Madrid this summer.
England defender Demi Stokes is back in the City squad, but striker Ellen White is still out injured, and midfielder Laura Coombs and goalkeeper Karen Bardsley are not ready to return to action.
Although Georgia Stanway trained on Tuesday, she will miss the Atletico game, but should be back for Sunday's WSL Cup derby with Man United.
The return leg in Madrid will be on Wednesday 30 October.
City and Arsenal, who are playing in the Champions League for the first time since 2013, are united in their ambition to end the four-year long domination of the competition by six-times winners Lyon.
The closest City have come to silverware was successive semi-final defeats by Lyon in 2017 and 2018, but Arsenal have at least lifted the trophy.
The Gunners now take on Slavia Prague in the Czech Republic capital, but do so on a bit of a down following Sunday's 2-1 loss at Chelsea.
It was only their second defeat in their last 14 competitive games, but it cost them their leadership of the WSL to City, who now have the only remaining 100 per cent record.
"Obviously we're a bit deflated. We need to turn it around quick in the Champions League. That's where our full focus goes to now.
"There's nothing better than having a game so soon after a game like Sunday's," defender Lisa Evans told Arsenal.com.
"Obviously, recovering players is going to be a big one," added Arsenal boss Joe Montemurro. "We've only had a three-day turnaround to work with.
"Most of our players played two games with their national teams so some of them haven't had much recovery, but that's football. That's the way it is. There's no excuses. We want to be in the professional game."
Their return leg will be at Meadow Park on Thursday 31 October.