Robben is officially listed as a 25-year-old, but his steady hair loss, middle-aged face and fondness for Classic Gold FM have raised suspicions that he may have forged documents.
After last night's 2-2 friendly against England, Robben came off the pitch struggling for breath and adopted a grave expression as he talked to Dutch TV presenter Joop De Groopstrap.
"I think the time has come to admit that I'm 40 if I'm a day," Robben panted. "This whole thing started from an administrative error when I was put in the Under-21 squad at the age of 39 and I just ran with it.
"But my body is starting to complain and I can't keep playing for ever, so I decided it was time to come clean.
"I hope people don't judge me too harshly but I don't think they will because everyone loved '17 Again' didn't they? Didn't they?"