Accusations that Lionel Messi is in decline are laughable, according to the Argentine's former Barcelona team-mate Gianluca Zambrotta.

Messi endured a difficult match against Juventus in the Champions League on Wednesday, firing five shots off target as Barca exited the competition at the quarter-final stage, losing 3-0 on aggregate.

But Zambrotta insists Messi's form is not slipping, comparing the Barcelona star to his great rival Cristiano Ronaldo, who scored five goals in Real Madrid's 6-3 quarter-final win against Bayern Munich.

"It makes me laugh when somebody says Messi is declining," Zambrotta told Omnisport.

"I don't know the accurate statistics but at this time in the season, if I am not mistaken, Messi and Ronaldo must have scored the same amount of goals roughly. They are on the same figures. 

"Messi in the Champions League has scored so many this season, the same in LaLiga. You can't say he is in Sunset Boulevard. Maybe he is more mature and understands that sometimes he has to pull the brakes, as we say."

Zambrotta suggests the number of games Messi plays for club and country may be having an impact, as he reminisced about playing for Barcelona between 2006 and 2008.

"When I was Messi's team-mate I knew he could be decisive at every moment," the former Italy international added. "In a nutshell, when you were in trouble you gave him the ball thinking... he'll do something with it. 

"In training instead you had to try and take the ball off him and sometimes I managed to do that when I was at the peak of my physical condition. You need to be at your best to do it but most of the time it was very hard to dispossess him of the ball.

"Messi now is not static. Maybe he wants to receive less knocks and tries to draw the others' attention towards himself to let his team-mates have more space. But mostly because he plays too many games.

"Messi is that type of player, playing in between 60 and 70 games per year. It is impossible to be always at the top. Him, Cristiano Ronaldo, they always play with their national team and their clubs, always going until the end of every competition."