Goals from Asisat Oshoala and Jennifer Hermoso, plus a Mariona Caldentey penalty, handed the Spanish Champions a strong advantage to take to Manchester in a week's time, while Chloe Kelly missed the chance to net a crucial away goal, as her second half spot-kick was saved well by Sandra Panos.
The result, which could have been harsher if not for Ellie Roebuck, means Gareth Taylor's side have it all to do in the second leg - against a side who have not conceded two goals in a game since the 2019 Champions League Final.
With both sides heading into the clash in scintillating form – FA Women’s Super League top scorers City having had won 15 of our last 16 in all competitions and Barcelona victorious in all of 20 of their domestic encounters, netting an astonishing 99 goals in the process – the tie promised to be a fascinating encounter, as two attack-minded, possession-based heavyweights locked horns.
City had been warned of a culture shock – not of the Italian environment we found so much to our liking in the Round of 16 against Fiorentina but of the fact the share of possession would be apportioned much more evenly.
In fact, the hosts – competition runners-up in 2019 – dominated the lions’ share of the ball in the opening quarter of the game and probably should have broken the deadlock on 17 minutes, as Oshoala found herself clean through but was denied superbly by the outstretched foot of Roebuck.
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The home side continued to press, peppering the City goal with shots which were well-defended by the brave bodies of the defence. Roebuck was called into action again with another excellent stop, palming away Aitana Bonmati’s goal-bound effort, as the Spanish Champions found plenty of joy down the right flank.
Shocked into action, City sparked into life and carved two good opportunities of our own. Caroline Weir was unfortunate not to gain the desired connection to half-volley a Sam Mewis cross home, before Chloe Kelly headed over the bar from Lauren Hemp’s delivery.
Roebuck continued to be the busier of the two ‘keepers though, thwarting Alexia Putellas twice by tipping an effort around the post and gathering a header from pinpoint range.
There was nothing the England international could do about the opener though, as Barcelona’s pressure finally told on 35 minutes when Oshoala swept in off the post.
The strike marked the first goal City had conceded since the first week of February against Arsenal – and it could have been two just eight minutes later when Roebuck denied Caroline Graham Hansen what looked a certain goal, smothering the ball as the Norwegian tried to round the shot-stopper.
At the other end, Mewis had a goal disallowed for offside but it was the closest City came to a leveller inside the opening 45.
The second period burst into a flurry of activity with two penalties awarded inside 11 minutes. However, both would endure contrasting results.
Barca were handed the chance to double their lead when Demi Stokes upended Oshoala, and Caldentey smashed the penalty past Roebuck.
Three minutes later, City were awarded a spot-kick, as the lively Lauren Hemp zipped her way into the box, drawing a foul by Maria Leon - but Kelly would prove unsuccessful from 18 yards, as Panos produced an excellent save.
The Barca shot-stopper then denied Ellen White before Mewis dragged an effort uncharacteristically wide, as City pressed for a vital away goal.
However, it was unfortunately just one of those days for the visitors and instead, it was the hosts who would strike again as Hermoso converted the rebound after Roebuck had forced Putellas' attempt onto the post.
City will need at least a 3-0 win on home soil next Wednesday to stay in the tie.
How we lined up...
Taylor opted to make a change from our 3-0 victory over Bristol City seven days ago, as Lucy Bronze was restored to the starting XI following a short injury lay-off.
Roebuck took her place in goal, shielded by a back four of Bronze, Abby Dahlkemper, Alex Greenwood and Esme Morgan.
Keira Walsh was employed in her defensive midfield role, sat behind Mewis and Caroline Weir, while Kelly and Hemp occupied the wings and White led the line upfront.
CITY XI | Roebuck, Bronze, Dahlkemper, Greenwood, Morgan (Stokes 46'), Walsh, Mewis, Weir, Kelly (Lavelle 70'), Hemp, White (C) (Stanway 70').
SUBS | Taieb, Keating, Beckie, Stanway, Mannion, Davies, Coombs, Park.
BARCELONA XI | Panos, Maria Leon, Torrejon (Crnogorcevic 79'), Mariona, Alexia, Patri, Bonmati (Hamraoui 70'), Leila, Graham Hansen (Martens 62'), Pereira, Oshoala (Hermoso 70').
SUBS | Font, Munoz, Losada, Serrano, Fernandez.
Player of the Match: Ellie Roebuck
While she may not be used to starring as the busier goalkeeper, the City and England shot-stopper produced a fine performance to keep the scoreline down - with nothing she could have done about any of the goals
Oshoala's opener was the first goal City had conceded in 608 minutes of action - just over 10 hours of action.
The clash also marked the first game in which we had failed to score in 15 matches.
City return to FA Women's Super League action on Saturday 27 March with a 17:30 (UK) kick-off at home to Reading.
Taylor's side then welcome Barcelona to the Academy Stadium in the Champions League quarter-final second leg on Wednesday 31 March in a 16:00 (UK) kick-off for a place in the last eight.
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