Antoine Griezmann spent 10 years at first club Real Sociedad before joining Atletico Madrid for a reported £24m in 2014
Griezmann became the sixth-most expensive player in history when he joined Barca for £108m in 2019.
He scored 35 goals in 102 games before returning to Atletico on a two-year loan at the start of last season.
The 31-year-old has three goals and two assists in 11 appearances so far this campaign, though only three of those appearances have been starts.According to Spanish football reporter Guillem Balague, there was a clause in Griezmann's loan contract that would oblige Atletico to buy the forward for 40m euros should he play more than 45 minutes in more than 50% of their games.
In response, Atletico boss Diego Simeone has used Griezmann as a substitute after 60 minutes in eight of his 11 appearances this season to ensure that clause was not triggered.
Griezmann could make his first appearance back as a permanent Atletico Madrid player against Club Brugge in the Champions League on Wednesday.
The 2018 World Cup winner is the fourth-highest scorer in the club's history with 144 goals in 304 appearances over two spells, having initially joined from Real Sociedad in 2014.
He was won the Europa League, Spanish Super Cup and Uefa Super Cup during his time at Wanda Metropolitano.
-- Courtesy of BBC Sport