Manchester United's all-time record goalscorer Wayne Rooney believes it will take another "two to three years" before the club can recapture the sort of glory the striker experienced during his time at Old Trafford. Rooney, United's record scorer with 253 goals, is set to face his old club in the FA Cup fifth round with Derby County at Pride Park on Thursday. He spent 13 years at Old Trafford, during which he won five Premier League titles, three League Cups, an FA Cup, and Champions League and Europa League titles. Rooney, 34, returned to boyhood club Everton in 2017 before embarking on a spell with Major League Soccer outfit DC United. He played his first game for Derby as a player-coach in January. The former England captain feels United are moving in the right direction under Ole Gunnar Solskjaer but need time before they challenge for major honours. "It is going to take another two or three years, I believe," Rooney told reporters. "The important thing is for them to try and get into the Champions League this year. "It is really tight at the minute. I think that will help them a lot if they can do that -- but it is going to take time. "The United fans need to be a bit patient with what's going on and let these players try and prove themselves. "They need to bring some players in, they need to also get rid of some players, and within two or three years they have to be challenging again." Derby, managed by former Dutch international midfielder Phillip Cocu, are 13th in the second-tier Championship and while Rooney knows the Rams are underdogs, he believes they can surprise his old club. While enjoying his current role as Derby's playmaker from a deeper midfield position, Rooney has his eye on a long-term future in the dugout. "I think it's a shame when you see great players walking away and not really having a go at management or coaching," he said. "I'm a player first and foremost and then a coach, to try and learn to help me in the long run."