Rare Swiss goal spree routs Wales
Valentin Stocker headed Switzerland in front after eight minutes but Gareth Bale broke clear of the defence to level for the visitors five minutes later.
The hosts regained the lead with a scrappy Marco Streller goal in the 21st minute, the lanky striker appearing to mis-hit a shot which flew fortuitously into the corner.
Switzerland added two more in the final 10 minutes as Gokhan Inler converted a penalty, awarded for a foul on Tranquillo Barnetta who appeared to over-react, and Stocker swept home Eren Derdiyok's pass with one minute left.
It was the first time in just over one year that the Swiss had managed more than one goal in a game and the first time they had scored four times in a competitive match since their 6-0 win over the Faroe Islands in 2004.
The Swiss, who took eight games to score their previous four goals, had been on a steady downhill run since their shock 1-0 win over Spain at the World Cup, reaching a low point by losing in Montenegro on Friday.