Kennedy, who had been hooked at halftime during City's home loss at Everton in the Women's Super League three days earlier, again looked at sea at the back as City's defence got run ragged by the defending European champions, who scored through Claudia Pina and then their two Ballon d'Or winners, Aitor Bonmati and Alexia Putellas.
It could have been much worse for the WSL challengers, as Barcelona rained in 30 shots to three in a hugely one-sided contest at the Olympic Stadium which made City's win in the reverse fixture back in Manchester at the start of October feel an awfully long time ago.
Barca's Alexia Putellas celebrates her side's third goal against City. (AP PHOTO)
Struggling with injury absences and without star striker Khadija Shaw, it proved a long night for patched-up City, who had to avoid a two-goal defeat to finish top of Group D ahead of the champs.
But they never looked likely to keep the hosts at bay, with playmaker Bonmati running the show and winning the player of the match award the night after picking up her latest award as the 'FIFA Best' women's player.
City's defence had looked like an accident waiting to happen as Kennedy three times gave the ball away before her failure to clear her ranks a fourth time gifted the ball straight to Pina, who put Barca ahead just before the break.
💥 PINAGOOOOOOOOOOL �— DAZN Women's Football (@DAZNWFootball) Barça take the lead over Manchester City just before the break.Watch live for free on DAZN ▶� https://t.co/dIfKpURfZv#UWCLonDAZN #UWCL pic.twitter.com/nOTMfp8mknDecember 18, 2024
City were then guilty of gifting the ball away again in the 57th minute, their sluggish rearguard again being picked off by Bonmati, who raced through and nutmegged busy keeper Khiara Keating with a low left-foot finish.
Putellas, who had won the previous two Women's Ballons d'Or prizes before Bonmati lifted two in a row, then made it 3-0 with a shot from outside the box in the 67th past the unsighted Keating.
Both sides finished on 15 points in their group, but Barca grabbed top spot with a superior goal difference.