The Ospreys lock has taken the difficult decision after a succession of injuries to his shoulder.
“I’m devastated, I hoped to have a long career and achieve a lot,” Martenko told the South Wales Evening Post. “It’s been one problem after another, I had two operations, then it went again and the doctors said I wouldn’t be able to lift my arm up if I kept on playing. The Ospreys have been brilliant, they did all they could to get me right, but it wasn’t to be.”
There were big hopes for the Tonyrefail-born second-row when he joined the Ospreys on a development contract from Pontypridd last summer. He had already hurt his shoulder while playing for Wales U21 and made just two substitute appearances for the west Glamorgan region, against Leinster and Connacht.
