Johannesburg - SuperSport United's battering ram Glen Salmon believes the playing surfaces in South Africa have compounded his injury woes.The striker is sidelined with a right knee problem and his long-term prognosis remains uncertain due to chronic tendinitis."I've never had this before and it is caused by overuse I am told," Salmon told the PSL's official website."I'm training on my own and doing different exercises so as to not aggravate it further. It is very frustrating as I want to play but unfortunately I can't, doctor's orders.""In Europe the fields are better maintained and not as hard as the turf we play on here. I think it added to my knee injury. I have strong legs and am used to playing with a defender on my back, so I am used to that but ja, it started last season and I must rest for a while now," he added.The 32-year old is out of action for an indefinite period and he admits this has left him and his manager feeling disgruntled."It's frustrating more than anything else. The coach wants me to play and he always asks how I am doing and when I will come back. He is also frustrated but unfortunately we cannot rush this," he said.After a long break, Matsatsantsa resume Premiership action on Saturday with an away trip to the Moses Mabhida Stadium where they will face AmaZulu.