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.
The Brazilian, 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 Arabia's Al-Hilal since moving from Paris St Germain for a reported fee of around 90 million euros ($97.90 million) in August last year.