Messi had failed to dovetail with other top strikers Samuel Eto'o, Zlatan Ibrahimovic and David Villa at the Camp Nou but took no time at all to gel with Suarez, who became his best friend at the club as well as a prolific strike partner.

"When I got to Barcelona everyone said be careful with Leo, that he was the main striker at the club," an emotional Suarez said at a news conference attended by Messi and fellow Barca teammates Gerard Pique and Jordi Alba.

"But in our time together we always tried to perform as well as we could and I can leave here feeling very proud."

Amid all the upheaval at Barca this summer - in which Messi appeared set to leave the club before he walked back on his threat to end his contract unilaterally - it emerged that Suarez did not feature in the plans of recently appointed coach Ronald Koeman.

Suarez lashed out at the media over their reporting on the two players' influence on the club.

"It has been a crazy month, many things have been said and leaked that were invented, many things that made me angry. But everyone knows how good a relationship I have with Leo," he said.

Suarez seemed set to join Italian champions Juventus, but a move to Turin collapsed after complications over his passport application, before Atleti swooped.

"I haven't yet imagined what it would be like to face Barca, against former teammates and friends, but we will try and have a good game," he said.

Suarez joined Barca from Liverpool in 2014 after making global headlines for biting Italy's Giorgio Chiellini in the World Cup, which meant he was banned for the first four months.

He won 13 major trophies during his six seasons at Camp Nou, including four La Liga titles, four Copa del Reys and the Champions League.

Suarez is third in Barca's all-time scoring list, with 198 goals in 283 games in all competitions.

"I'm grateful to the club for trusting in me in 2014 after I made an error, it wasn't easy to accept that and they treated me marvellously since I arrived," Suarez said.

"I came here to fulfil a dream, to play for the best club in the world and I should be very proud of everything I did.

"I suffered a lot but I'll remember the good times, the goals I scored alongside the best player of all time."

Australian Associated Press