DOHA: Yet another World Cup has ended in tears for Neymar, with football's most expensive player hinting he may not pull on the Brazil shirt again following a painful defeat to Croatia.The 30-year-old, who gave Brazil the lead during extra time of their quarter-final in Doha with a brilliant individual effort, was distraught after Croatia triumphed on penalties.Speaking to reporters, his voice trembling with emotion, he admitted he could not "100 per cent guarantee" he would be seen in the famous yellow shirt again.Neymar, who has 124 Brazil caps, will be 34 by the time the next World Cup comes around in North America in 2026.That is still younger than many leading names in Qatar, from Lionel Messi and Cristiano Ronaldo to Luka Modric and Olivier Giroud.But Brazil's brittle number 10 hinted last year that he would not appear at another World Cup, suggesting in one interview that he might not have the mental strength "to put up with even more football".Neymar has carried the hopes of a nation into three World Cups since his emergence as a generational talent at Santos.He has scored eight World Cup goals but the tournament has exposed his vulnerable physique and fragile emotions.In 2014, playing on home soil, he was cut down in a quarter-final win over Colombia and stretchered off in agony with a fractured bone in his back.Without him Brazil capitulated, losing the semi-final 7-1 to Germany.Four years ago, Brazil's build-up to the tournament in Russia was dominated by his battle to recover from an operation on a broken bone in his foot.He came back in time, but that World Cup was still remembered for his tears in a win over Costa Rica before the Selecao lost in the quarter-finals to Belgium.This time he appeared to be in