Ruud van Nistelrooy backs Robin van Persie to guide Manchester United to Premier League title So there could be no be higher authority to pronounce upon the prodigious form of compatriot Robin van Persie. "It feels like he has been here forever," said the retired striker, who also predicted that his successor at Manchester United could be the critical figure in bringing the club a 20th league title. "As he's proving right now, he is making the difference on many occasions," Van Nistelrooy said. If he can keep going like this through the whole season then I can see United landing another championship win. He got his first goal quickly and has not stopped since, so I hope it will continue. It's important for any striker at a new club to start putting the goals in, and then you go on from there. That's what happened to Robin. He has the experience of the Premier League already and he has proved to be a great signing. With the way he plays, he fits in really well at this club. Van Persie scored 11 goals in his first 14 appearances for United: a ratio that easily keeps pace with his predecessor's average of 30 strikes a season. A measure of his lethal threat is that he heads into Wednesday's home clash with West Ham seeking to end a rare fallow period, having not found the net for three games - not since April 2010 has he gone four matches without scoring. Arguing against those who saw Van Persie's £24 million summer transfer from Arsenal as a gamble, Van Nistelrooy said: "He has proved those people wrong already. I was close to him playing in the Dutch national team and I was convinced of his qualities then. It's great to see, the way he plays - he fits into United's playing style. He's everywhere, involved in the play and in the finishing, too, so that makes him special. I'm happy that I've hung up my boots now and I can enjoy watching him play. I spoke to Robin a little while ago and congratulated him on his fantastic start. I wished him well and told him to carry on like this. As for himself, Van Nistelrooy has switched to a quieter life in the sunshine of Marbella, but harbours a regret about how abruptly his United career ended. The 36 year-old was jettisoned by Sir Alex Ferguson in the summer of 2006, driving away from Old Trafford in high dudgeon when the manager selected Giuseppe Rossi ahead of him. He had never been back in six years, until he decided to bury old grievances by attending the unveiling of Ferguson's statue last Friday. "I left here quickly," admitted the Dutchman, who concluded his playing days with Málaga in May. Sometimes in football, you don't have time to say goodbye to people you have spent time with. So that was sad, leaving without saying thanks to the fans and everybody who supported me during all those years. But after six years, it is great to be back and see them again. This is my first year in 20 not playing. Maybe I will do some coaching in the future, but I don't miss playing because I went right through to the end realised enough was enough. I couldn't go any further and accepted it. I have moved on and I didn't have the feeling that I still had more in me.