The Olympic champion Kazuyoshi Funaki, of Japan, had to settle for second place in the final standings, despite finishing fourth yesterday. The Slovenian clinched the overall title with 1,253 points, while Funaki gained 1,234.
Kasai soared 147.5 metres in his first jump to set a hill record and landed a leap of 131 in the second series for a winning total of 298.3 points.
Second place also went to a Japanese jumper, Hiroya Saito, who collected 296 points for leaps of 138 and 136.5 metres.
By finishing ahead of Funaki, Kasai and Saito effectively prevented their Japanese teammate from clinching the overall title. He was trying to become the first Japanese to win the title.
Peterka, who had a slow start on the circuit, finished the season with a flourish, scoring four wins to retain the title. The 19-year-old Slovenian flopped his second jump, landing only 115.5 metres when he was hit by a tail wind. But 40,000 home fans were still able to rejoice.