Ole Gunnar Solskjær has admitted Manchester United’s lack of cutting edge is a “worry” after his side were held to a third successive goalless draw to leave them 14 points behind the leaders Manchester City before the derby on Sunday. United managed one shot on target at Selhurst Park in a lacklustre display that followed another drab stalemate at Chelsea on Sunday and the 0-0 draw against Real Sociedad in the Europa League last week. “Of course you are not happy if you don’t create enough chances to win a game,” Solskjær said. “It’s been a week with no goals and sometimes three games without scoring sounds like a lot. It’s a bit of a worry but because we play every few days I know the boys are giving everything. Attitude and approach I’m very happy with but the quality we need to get back to what we know we can do. “The tempo was missing, once in a while it happens. It wasn’t one of our best nights, that’s for sure. Roy Hodgson always sets his teams up to be really hard to play against and it just showed again tonight. We just have to find a spark again, the quality again and try and win the games.” A last-minute save to deny Patrick van Aanholt by Dean Henderson – playing after David de Gea was forced to miss the match because of personal reasons – ensured Palace have still yet to record a home victory against United in the Premier League in 12 attempts. Solskjær refused to be drawn on whether the Spaniard would be back for the derby but he said Henderson has proved himself to be a good understudy. “I can’t really say about David – it’s of course a private matter. But Dean is ready if he is called upon. He kept his concentration and saved us a point because that was probably the best chance of the game. We really needed him.”