Gemma Bonner’s first City goal opened the scoring, but Kenti Robles’ last-minute strike cancelled out the the Blues' earlier effort to set up an intriguing second leg.
Bonner's away goal could prove crucial as the tie comes to Manchester at the end of the month.
City started brightly with Mel Lawley performing a lung-bursting run down the wing after just two minutes of play. Following a quick one-two with Nadia Nadim, Lawley tried her luck with a shot at goal but Dolores Gallardo punched it away to prevent an early lead.
Atletico continued to test us at the back throughout the first half and tested Karen Bardsley on a number of occasions. One of those being in the shape of Silvia Meseguer’s curling effort from just inside the box, which our ‘keeper blocked well.
It didn’t take long for the Blues to break the deadlock as Bonner launched into the air to head home Caroline Weir’s superb corner – marking the defender’s first goal since joining the club during the summer transfer window.
The home side launched into action following Bonner’s opener and Bardsley was called to action once again as Amanda Sampedro’s thunderous strike sailed towards the top of the goal, but the England international stretched to push the attempt over the crossbar.
City responded immediately, as Lawley continued to work tirelessly down the left flank. Our winger burst through the defence hunting for a chance but took just a few seconds too long which meant the Atletico ‘keeper Gallardo had time to pounce onto the oncoming ball to prevent City from doubling their lead.
As the break approached, Atletico looked like they were closing in on an equaliser, with Tessa Wullaert forced to clear Elena Linari’s ball off the line and Bonner forced to intercept Ludmila Da Silva as she was about to launch a close-range strike.
The Spanish outfit made their mark in the second half, constantly driving forward and causing our defence a number of problems, particularly Da Silva – whose speed and agility tested Abbie McManus and Jen Beattie on the right consistently.
Bardsley did incredibly well to prevent Da Silva from taking the score level in stunning fashion as our goalkeeper chested away the Atletico striker’s header – prompting a huge reaction from the crowd.
As Atletico dominated, it was substitute Claire Emslie who looked most likely to score City’s second on the counter-attack as she fired a curling shot towards goal but the Scotland international was unlucky to see her effort swerve just off the target.
Despite City’s best efforts, Atletico equalised in the final minute of the game through Robles, whose soaring cross deflected over Bardsley and into the net, frustrating for the Blues, who had battled for much of the second period.
How we lined up
Bardsley took her place in goal, shielded by a back four of Mie Jans, Bonner, Beattie and McManus.
Skipper Keira Walsh occupied her defensive midfield role alongside Wullaert and Weir.
Nadim led the line up front, flanked by Lawley and Nikita Parris, who made her 100th appearance for the Club.
Next, Nick Cushing’s side travel to Bristol in the Continental Cup on Sunday 16 September, kick-off at 3pm (BST).
The Champions League Round of 32 second leg clash at the Academy Stadium takes place on Wednesday 26 September (7pm BST).
Tickets for all of City's home games are available via tickets.mancity.com or at the Etihad Stadium Ticket Office.