Messi still recovering from hamstring injury that basically started after those tackles at Copa America especially the 6 yellow cards of Colombian players that were all from tackles on him. He's still never look quite right since then. There's two reasons here... Firstly, he didnt manage himself well by keep playing for Argentina even when not needed, secondly, preasure from PSG to play as many games as possible. So he has no option now but to keep playing even if still injured since Leonardo already made a remark when Messi decided to travelled for that latest qualifier round and he basically did nothing in those 2 games. Poor decision.