Argentina coach Gerardo Martino has suggested that Lionel Messi is currently dealing with the mental and physical results of having been the focal point in so many games over the last decade for club and country.
Messi, 27, has already played over 500 senior club and international matches since making his Barcelona debut in October 2004 -- winning every trophy available with the Camp Nou club, and playing in three World Cups with Argentina.
The four-time Ballon d'Or winner was troubled by persistent muscle problems throughout the 2013-14 season, but has been fit enough to start all his club's La Liga and Champions League games so far this term.
Messi has scored 21 times in those 21 outings, but high-profile teammates including summer signing Luis Suarez have not been delivering nearly as often, and Barca have slipped four points behind leaders Real Madrid in the La Liga table.
Messi's current international manager, and his club coach during the 2013-14 campaign, said in an interview with the DPA news agency that the psychological strain of being always looked to by teammates to decide games was huge.
"A very important thing is the 'wear and tear' he has had for 10 years, averaging 60 or 65 games per year," Martino said. "He plays a lot of decisive games which wear you out physically and psychologically. He has an extra load that no other player has. Everyone is waiting on him to resolve games, something that is very hard to change. We coaches must try to find ways of playing so that he is the most important part of the team, but not the saviour."
Martino said that although Messi is surrounded by so many big stars at Barcelona, including World Cup-winners such as Xavi Hernandez and Andres Iniesta, and Brazilian starlet Neymar, his teammates still expect him to deliver all the time.
"I believe there is more expectation on the part of his teammates at Barcelona than those of the national team," he said. "I always said that at Barcelona it was better due to the teammates he had. The reality is that also at Barcelona everyone ends up waiting for him to decide many things. The situation is not that different than the national team."
Martino tried to play Messi in a number of different positions during their time together at club level, and since taking over as Argentina boss last summer has often started his No. 10 out towards the right wing. Current Blaugrana coach Luis Enrique has also tried something similar, with former Liverpool attacker Suarez currently positioned at centre-forward.
In the end Messi tended to play where he himself felt he could do most damage, Martino said.
"He is unpredictable as a player," he said. "It is very difficult to establish what we will find. You can think that with time he will play a bit deeper, without so much explosive impact, and he has done that. Or you could imagine him out on the wing, with more chances to take on opponents one against one. And he has done that too.
"Everything that happens around Lionel happens solely and exclusively for how he is feeling himself."