The midfielder, dogged by injuries over the last year, has been recovering from a virus that has kept him sidelined since November.
Development coach Clive Allen said: "It's fantastic to see him back. He's worked very, very hard and his attitude has been superb - you just hope he gets some good fortune.
"I just hope he enjoys it. We're easing him back into it in terms of the match situation but I know he's looking forward to it and we're glad to see him back.
"He wants to play, it's been a very frustrating time for him and everyone understands that with the injuries he's had.
"He's an international class player and a great asset to the club when he's fit, so we're hoping he's come through okay, builds on it and gets fitter and fitter."
Simon Davies is set to return to action for the reserves at Crystal Palace on Tuesday night.