Scotland manager Gordon Strachan may not be able to call on Craig Gordon in the future for 'keeper duties as the ex-Hearts man has admitted a knee problem may force him to retire. Gordon has failed to find a new club following leaving Sunderland at the end of last season. Two broken arms and the knee injury did not help his playing on a regular basis on Wearside and the ongoing problem with his leg has meant he has been without a club this season. Dumbarton manager Ian Murray gave him a seat on the backroom team's bench on Saturday after taking up an offer to help out on an informal basis and he admits coaching could be his future. Gordon said: "It's very unlikely I will be playing again this season. In fact I'm not sure if I'll play again, so I'm looking to get into coaching as I want to remain in the game. I'm not ruling out playing again, but I need to get things in place if the news is not good in that respect. I've had a couple of surgeries on it (knee), but it's definitely not back to 100 per cent yet. Hopefully I can get back to playing with a bit of pain. It's about getting to a stage where I can get what I need to out of the knee. That's part of the reason I wanted to go into coaching, you don't know when the end might come for playing. I'm certainly not ready to throw in the towel just yet but it's been a long time and I don't know where I'll be going in the future."