Gerard Pique scored the only goal as Barcelona beat Dynamo Kiev 1-0 at Camp Nou to get off the mark with their first victory in this season's Champions League.
Barca had lost their opening two group games for the first time ever, going down 3-0 to both Bayern Munich and Benfica, but they were good value for the three points.
Pique volleyed in a first-half opener to end a run of 287 minutes without a goal in the competition for the Catalans and they looked comfortable without adding to their scoring.
The win moves Ronald Koeman's men above Kiev into third place in Group E, a point behind Benfica and three off Bayern Munich, with those two sides meeting later on Wednesday.
Barca had recorded fewer shots on target (one) than any side in the competition heading into gameweek three and that lack of cutting edge was again on show as Sergino Dest failed to test Georgi Bushchan with a close-range header early on.
Luuk de Jong was also off target with a headed attempt from six yards, though the striker did at least manage to force Bushchan into a first save three minutes later with a curled shot from the edge of the box.
The hosts' breakthrough duly arrived through Pique with 36 minutes played, the centre-back being left in space to guide in Jordi Alba's latest exquisite cross with a first-time finish.
Ansu Fati, brought on for the ineffective De Jong at half-time, wasted a good chance to score Barca's second when getting his angles all wrong and sending an overhead kick wide of the target.
Barca could not fashion any more opportunities, but the Ukrainian champions failed to ask any questions of their opponents, not registering a single shot on target as Pique's goal proved the difference.
What does it mean? Barca finally building momentum
Having lost back-to-back group games in a single Champions League campaign for the first time since 2000-01, Koeman accepted this was a must-win contest for his side.
Barca have a good recent record against Dynamo, including wins home and away against the Ukrainians last season, and they were never really in trouble in this contest – even if they only had one goal to show for their relative dominance.
It marks the first time Koeman's side have won back-to-back games in all competitions this term, giving them some momentum ahead of Sunday's huge Clasico with Real Madrid.
Old-timer Pique inspires Barca
Almost exactly a year on from his last Champions League goal, against the same opponents at the same ground, Pique scored the all-important breakthrough goal for Barcelona.
As well as becoming Barcelona's oldest Champions League goalscorer at 34 years and 260 days, Pique is now also the joint-leading goalscorer among defenders in the competition's history, level with Roberto Carlos (16 each).
Delightful Depay
Not for the first time this season, Depay was Barca's best attacking player on the day as he laid on five big chances for his team-mates – no other player on the field created more than three.
Compatriot De Jong made way at the interval after finding the target from only one of his four attempts, while substitutes Fati and Sergio Aguero managed only two efforts between them in the second half.
What's next?
Barcelona have that huge showdown with Madrid to come on their return to LaLiga action on Sunday, the same day that Kiev take on Dnipro-1 in the Ukrainian Premier League.
