'upset'.

Yesterday my wife 'came across' this term in her weekly newspaper. She was reading an article on tennis in the 'Asahi Weekly'. Specifically,the piece concerned Kimiko Date-Krumm.She recently won a tournament at the 'ripe old age' of 38 (and 11 months). Usually most professional sports people are considered 'well past their prime'as they approach/reach their mid-30's. So,it is a fantastic achievement,but my wife was confused with the way 'upset' was used in the article. Do you know what it refers to here? Today's photo was taken from the top of Durham Cathedral in County Durham,England.