Neymar was not too downcast after being forced to leave Monday's Asian Champions League Elite match due to injury with the Al Hilal forward saying he felt the issue was nothing more than a strong cramp.

Brazil forward, who limped off 30 minutes after coming on as a second-half substitute in Al Hilal's 3-0 win over Esteghlal, said doctors had warned him about the potential for muscle issues following his return from an anterior cruciate ligament (ACL) injury.

The 32-year-old returned to action two weeks ago, having been out since Brazil's CONMEBOL World Cup qualifier against Uruguay in October last year when he suffered the injury.

"It felt like a cramp, only very strong!" Neymar posted on Instagram. "I'm going to have some tests and I hope it's nothing too serious.

"It's normal for this to happen after a year, the doctors had already warned me, so I have to be careful and play more minutes."

Neymar has played only seven games for Saudi Pro League side Al Hilal since moving from Paris Saint-Germain for a reported fee of around 90 million ($97.90m) in August last year.