#3 Alexis Sanchez
When Barcelona signed Alexis Sanchez from Udinese for €26 million in 2011, the Chilean was still a raw talent but had the potential to develop into one of the brightest young players in Europe.
Sanchez's dribbling, pace, work-rate, goal-scoring and versatility made him a massive asset for Barcelona during his three years with the club. After taking time to settle at Camp Nou, Sanchez quickly became one of the club's main goal-scorers.
He scored 19 goals in 34 La Liga appearances in his final season with the club, and was arguably ready to become the main man at Barcelona. The Chilean was, however, denied the chance to shine due to the presence of Lionel Messi, and was sold to Arsenal in 2014 for £32 million.
Sanchez went on to become one of the best players in the Premier League during his time with Arsenal, where he was given the chance to become the club's star player.
#2 Neymar
Neymar was arguably one of Barcelona's best signings in recent history. The Brazilian superstar was groomed to take over the reins from Lionel Messi at Barcelona. Neymar, along with Messi and Suarez, formed one of the most formidable attacking trios in the game.
During his four seasons with the club, Neymar scored 105 goals in just 187 appearances in all competitions. He helped the club win two La Liga titles, three Copa del Reys and a Champions League.
Despite being happy while at Barcelona, Neymar was never the main man at the club. PSG spent €222 million to sign the Brazilian from Barcelona in the summer of 2017, a record transfer that shocked the football world.
Neymar joined PSG in the hope that he would be able to lead the club into a new era, and step out of the shadow of Lionel Messi.
#1 Zlatan Ibrahimovic
Barcelona signed Zlatan Ibrahimovic from Inter Milan in exchange for £59 million and Cameroonian striker Samuel Eto'o. Ibrahimovic was one of the most lethal strikers in Europe and the main man at Inter Milan prior to his move to Barcelona.
Despite boasting an impressive record during his sole season with Barcelona, Ibrahimovic endured a fractured relationship with Barcelona manager Pep Guardiola. The two were not on speaking terms during Ibrahimovic's final days with the club.
Following Barcelona's semi-final defeat to Inter Milan in the Champions League, Ibrahimovic revealed how he confronted Pep Guardiola in the dressing room.
"I yelled, 'You haven't got any balls!' and worse than that I added, 'You can go to hell!' I completely lost it, and you might have expected Guardiola to say a few words in response, but he's a spineless coward. He just left, never to mention it again, not a word', said Ibrahimovic.
Zlatan Ibrahimovic revealed in his autobiography 'I am Zlatan', that Lionel Messi's insistence on playing through the middle rather than as a right winger led to the Swede's decline at Barcelona.
Messi was the focal point of Barcelona's attack. That led to Ibrahimovic moved to the flanks.