Sunderland boss Roy Keane has ordered his players to clean up their act as they attempt to resurrect their Premier League season.The former Manchester United skipper will send his team out against Portsmouth on Sunday desperate for a maximum haul after seeing them slip back into the relegation zone with a 1-0 defeat at Blackburn on January 2. Last weekend's 3-0 FA Cup defeat by Wigan at the Stadium of Light did little to lift spirits on Wearside, and meant the club has tasted victory only twice in its last 16 games in all competitions. That will have to improve dramatically if the Black Cats are not to find themselves entrenched in a tooth-and-nail battle. Keane has spent the last few days trying to bolster a small squad - loan signing Jonny Evans played against Wigan - but admits needless disciplinary bans have not helped, with injuries also biting hard. Greg Halford twice, Paul McShane, Liam Miller and Dwight Yorke have already been dismissed, while Dickson Etuhu picked up five bookings in his first eight games for the club. Keane said: 'Of course, we do have to look at it. Some of our yellow cards and our sendings-off, I really think we have no-one to blame but ourselves. 'You look at Blackburn - we had an opportunity to win the game, we didn't take it and then Dwight gets sent off, a player with all his experience. 'I had no arguments with the sending-off, don't get me wrong, but we had Liam sent off a few weeks ago against Chelsea right in the last minute, he lost three games, we had Paul McShane sent off in the last minute at Arsenal and we lost him for three games, so we have no-one to blame but ourselves. 'That's something the players have to look at because, with the injuries we have, we cannot afford to be having players suspended. The combative Etuhu, who is now away with Nigeria for their African Nations Cup campaign, in particular found it tough staying on the right side of referees during his early weeks in the top flight, prompting a word in his ear from a manager who knows a thing or two about life in the engine room. Keane said: 'It helps when you have a word with them and you give them a little bit of a warning. 'Some of Dickson's yellow cards could have been stopped. The only reason Dickson was not booked at Blackburn was because he did not play. 'He is away for the African Nations Cup, so hopefully he will not be booked for the next few weeks. 'I guarantee he is going to be booked in the African Nations Cup, but I cannot do anything about that.' Yorke will return from suspension, while Keane will hope for better news on Danny Higginbotham, Ross Wallace, Kenwyne Jones and Michael Chopra, who all missed out through injury last weekend.