Sunderland midfielder Dwight Yorke admits he is playing for his future at the Stadium of Light. The 36-year-old is out of contract at the end of the season and does not know whether he will be offered a new deal. He will spend the next few months working to help the Black Cats preserves their Premier League status and then see what his efforts bring. Yorke said: 'Who knows what is in store for me next year? 'My contract runs out at the end of the season and I will have to sit and see what happens. Will there be an offer here for me? I don't know. 'In the meantime, I have just got to keep trying to do my best for Sunderland Football Club until the end of the season.' Yorke will celebrate his 37th birthday in November - Blackburn midfielder Tugay and Derby defender Alan Stubbs are the only older outfield players in the top flight - knowing his career is gradually drawing to a close. But he remains an important member of manager Roy Keane's squad - he has missed the last two games with a calf problem but returned to action for the reserves last night to stake his claim for a start at Portsmouth a week on Saturday. Keane sprang something of a surprise when he brought his former Manchester United team-mate back to England from Sydney FC in August 2006. Yorke, however, had enjoyed an excellent World Cup finals campaign with Trinidad and Tobago in the midfield holding role, and that is a position in which he has prospered on Wearside. He was a key figure in the club's victorious Coca-Cola Championship campaign last season and has started 16 games to date this time around. The former Aston Villa star admits life in the second tier of English football came a culture shock, and is far happier to be playing his football in the Premier League. But he insists he would not be doing so if he felt he could not still contribute. Yorke said: 'If I didn't think I could be playing there, I would happily walk away from the game today. 'I felt I could play in this position I am playing today, and I feel I can compete with some of the young lads still. 'I will keep going until the moment comes when I cannot help the team or contribute to the team in any way. Then, I will certainly walk away. 'Right now, I am still enjoying the game - even though I would like to win a few more matches, which would make life a lot easier for all of us.' Sunderland, without the injured Yorke, gave their survival hopes a major boost on Saturday when they defeated Wigan 2-0 to claim their fifth home league win in seven attempts.