Barcelona was hopeful of renewing Messi's contract before the June 30 deadline, however it has not been yet and as a result, the 34-year-old is now officially a free agent, reported Goal.com.
The 36-year-old Chhetri has brushed aside any comparison with Messi whom he has overtaken to be the second highest international goal-scorer among active players.
Barcelona's sixth league win in a row lifted it back into second place at seven points behind Spanish league leader Atlético Madrid, which has two more games to play.
According to Spanish newspaper El Mundo, Messi would receive a maximum of 55,52,37,619 euros ($67,39,19,105) over four seasons, if a series of conditions were met.
The esteemed line-up includes Brazil's three-time World Cup winner Pele and legendary Argentinian Diego Maradona, who died last month of a heart-attack.
Messi took off Barcelona's blue-and-burgundy to reveal the red-and-black of Maradona's jersey from his stint at Newell's Old Boys duirng a match against Osasuna
In 58th minute, Giovani Lo Celso pulled the ball back for captain Messi to sidefoot low into the net, but the goal was eventually disallowed by the Brazilian officials for a foul by Gonzalez at the beginning of the move
