Following this stunning turn-around of fortunes for Barcelona, here is a flashback of some of the best come-from-behind wins recorded in Europe's premier club competition.
Luis Suarez feared he had destroyed his career and that Barcelona would not want to sign him following his four-month ban for biting at the World Cup.
Barcelona coach Luis Enrique is still not satisfied despite winning five trophies in 2015 and is aiming to do even better next year.
It was Messi's 56th converted penalty in La Liga and saw him draw level with Hugo Sanchez as the league's second-top penalty taker, behind record holder Cristiano Ronaldo on 61.
Barca are also planning to offer new deals to forwards Lionel Messi and Luis Suarez, and midfielder Ivan Rakitic before the end of the year.
Neymar's record-breaking 222 million euros ($263 million) transfer from Barcelona to Paris St Germain is set to be completed this week with the French club poised to pay his release clause.
Atletico Madrid won the La Liga title for the first time since 2014
Lionel Messi scored twice as La Liga champions Barcelona saw off a persistent Valencia side, who had Eliaquim Mangala sent off in the first half, to win 4-2 on Sunday and stay on the heels of leaders Real Madrid.
Barcelona lost for the second straight La Liga game in a 1-0 home reverse against Celta Vigo but there was no such trouble for Manchester City, who beat 10-man Manchester United 1-0 thanks to Sergio Aguero.
'I'm fine, my family are fine. We're at home, as everyone has to be. We are spending time together, even though it's not a pleasant situation. My family are fine in Germany, we phone and video call each other'
The most impressive players at the FIFA World Cup 2022 after Round One.
News of all that's transpired on and off the football field.
Barcelona and Brazil striker Neymar has launched an attack on his former club Santos and spoken out in support of his father, insisting he had the right to make millions from the player's transfer last year.
English Premier League side Manchester City's revered manager Pep Guardiola on Saturday sent an emotional message for Indians, saying his team was playing for them on the pitch and urged them to stay strong in their fight against COVID-19.
Barcelona were held 1-1 at home by Napoli in the first leg of their Europa League knockout stage playoff
A summary of sports events and sports persons, who made news on Wednesday
Defending champions Bayern Munich must face Diego Simeone's Atletico Madrid after they were drawn together in Champions League Group A alongside Salzburg and Lokomotiv Moscow.
Barcelona eased into the King's Cup last 16 when goals from Pedro, Cristian Tello and Neymar secured a 3-0 second-leg victory at home to third-tier Cartagena on Tuesday for a 7-1 aggregate success.
These and many more stunning photographs are encapsulated in this weekly, striking photo feature put together by Rediiff.com.
From a Sri Lanka cricket legend Kumar Sangakkara's final Test innings, Virender Sehwag's felicitation ceremony, FC Barcelona's Luis Suarez celebrating the La Liga title with his family, these and many more scintillating moments are frozen in time in this beautiful photo-feature.
News of all that's transpired on and off the football field
Beat Mexico's Tigres 1-0 to win their sixth title.
If you ask Barcelona and Spain fans about their most cherished footballing memories over the past decade the chances are they will involve an exquisite intervention from midfield maestro Xavi.
'I feel as confident and motivated as at the beginning. I can't control rumours, but I still have faith'
News of all that's transpired on and off the football field
Coach Ernesto Valverde and midfielder Sergio Busquets were due to give a news conference before the training session but spoke to the media after training due to their late arrival.
Barcelona coach Luis Enrique has given his backing to Xavi and says the veteran midfielder remains a valuable member of the squad despite having played just 45 minutes in the opening five La Liga games.
Lionel Messi was in inspired form as champions Barcelona hammered Celta Vigo 5-0 on Saturday, recording a fourth straight league victory which keeps them top of La Liga after Real Madrid had put the pressure on the Catalans with a 4-1 win at Eibar.
Bayern Munich midfielder Thomas Mueller has tested positive for COVID-19 and will miss the Club World Cup final against Mexico's Tigres UANL on Thursday
Reaction to the death of football great Johan Cruyff, who died in Barcelona on Thursday following a five-month battle with lung cancer.
As Leicester City celebrates its unexpected title triumph, Bikash Mohapatra/Rediff.com lists similar success stories across Europe's top leagues.
Atletico Madrid secured a berth in the Champions League group stage for next season and Deportivo La Coruna narrowly escaped relegation when they came from two goals down to draw 2-2 at champions Barcelona on the final day in La Liga on Saturday.
Barcelona's 2-1 loss at Ajax Amsterdam in the Champions League last week was down to a lack of intensity while Sunday's 1-0 reverse at Athletic Bilbao in La Liga exposed their relative physical frailty.
News of all that's transpired on and off the football field on Saturday
News of all that's transpired on and off the football field
Union Berlin's Paul Jaeckel scored a 76th-minute winner to give his team a 1-0 victory at VfB Stuttgart on Sunday and send them two points clear at the top of the Bundesliga.
Barcelona came through a testing local derby at Espanyol, winning 3-0 to cling to their slender lead at the top of La Liga after rivals Real Madrid had set the challenge by beating Valencia 2-1 in the earlier kick-off.
News of all that's transpired on and off the football field
The last-16 knock-out round kicks-off this week with Chelsea visiting Paris on Tuesday; Zidane to coach Real Madrid as manager in his first match in Europe