BRUSSELS (REUTERS/AFP) - Belgian footballer Gregory Mertens is critically ill in hospital after collapsing on the pitch during a reserve team match for Sporting Lokeren, his club said.

The match against Genk was 15 minutes old when Mertens collapsed.

Belgian media said he had suffered cardiac arrest and received CPR on the pitch, leading to the match being abandoned.

The reports said that Mertens had been placed in an induced coma in an effort to save his life.

"Our defender was immediately assisted by the medical team of Sporting Lokeren and KRC Genk," a statement read.

"He was transferred to the hospital in Genk.

"Sporting Lokeren sympathises with the family and hopes for a positive outcome."

Club doctor Kris Peeters was quoted by website Nieuwsblad.be as saying the 24-year-old Mertens was in a critical condition.

"Everything points to a cardiac arrest," Peeters said. "I am in constant communication with the treating physicians in Genk. The state of Gregory is still critical."

Chelsea's Belgium international goalkeeper Thibaut Courtois offered his support on Twitter, along with other players. "Keep fighting Gregory," Courtois said.

Mertens began his career in Brussels with Anderlecht, but moved to Bruges in 2011 before transferring to Lokeren in January 2014. He was capped several times for Belgian national youth sides.