Noren needed a birdie on the 18th hole at Celtic Manor Resort to stay a step ahead of Hansen, who shot up the leader board with a five-under 66.
Noren, who led after two rounds, heads into Sunday's finale at eight-under 205 for the tournament. Hanson and Hansen are tied at 206.
Defending champion Graeme McDowell started Saturday's round in second place but swooned with a 10-over round of 81 that included a quadruple bogey on the 12th hole.
Noren had some harrowing moments himself Saturday. He carded four bogeys on the front nine and needed four birds on the back side to finish even for the day.