Lionel Messi and Luis Suarez ran riot against Roma, helping Barcelona to a stunning 6-1 Champions League victory that assures them of first place in Group E with a game to spare.
Suarez opened the scoring after 15 minutes of the match at Camp Nou on Tuesday and Messi struck three minutes later on his return to the starting line-up.
BATE Borisov's draw with Bayer Leverkusen earlier in the day meant Barca were already sure of a place in the last 16, but the victory means they have wrapped up top spot ahead of their final game against the Bundesliga side.
Despite only having five points from as many games after a harrowing 90 minutes which also saw Edin Dzeko miss a late penalty before then netting a consolation, Roma are still in pole position to qualify in second place.
The Italians now have to better Leverkusen's result against Barca when they play BATE to reach the knockout rounds.
Barca then took the lead when Dani Alves surged down the right to latch on to Neymar's excellent precision pass and squared for Suarez, who tucked the ball into an empty net at the far post.
It was two for Barca just three minutes later. Messi exchanged two passes with Neymar before Suarez's chip sent him through and the skipper applied a dinked finish over Szczesny to cap a wonderful move involving the front three.
Barca dominated possession for the rest of the first half and made it three one minute before the break. Neymar's cross was headed out by former Blaugrana man Seydou Keita and Suarez unleashed a lethal volley into the far corner which had Messi applauding.
The home side made a fast start after the break, with Szczesny getting up to push Neymar's effort away from the top corner.
On 56 minutes, Neymar and Suarez combined to feed Messi and he squared for Pique – who was still up from a corner – to tap home before the defender was immediately substituted.
Barca made it five three minutes later. Neymar found Suarez from the left and the Uruguayan's shot was helped towards goal by Messi. Szczesny did well to save, but the returning star converted the rebound.
The forward only had himself to blame for not scoring on 77 minutes, though, when Barca were awarded a chance from 12 yards. After winning a penalty himself from Salih Ucan's foul, his poorly struck spot-kick was saved by Szczesny but Adriano was on hand to slam the rebound into the roof of the net.
Roma were given a chance to get on the scoresheet themselves when Dzeko was brought to the ground by Thomas Vermaelen, but Ter Stegen got down to save the striker's effort and - unlike Adriano's goal - there was no-one on hand to convert the loose ball.
Dzeko did find the net in stoppage time, heading into the bottom corner after getting on the end of Lucas Digne's cross from the left, but it was the merest of consolations for the reeling visitors.
