Hämeenaho started playing ice hockey at the age of four.[4] He played youth hockey with Kajaanin Hokki until the family moved to Ylivieska, where he and his brother joined the Ylivieskan Jääkarhut [fi] organization.[5][6]
In April 2022, Hämeenaho signed a three-year SM-liiga contract with Ässät.[7] He made his SM-liiga debut at 17 years old on September 14, 2022, in the opening game of the 2022–23 season against Tampereen Ilves. Playing right wing on Ässät's fourth line with Kalle Myllymaa and Niklas Appelgren, Hämeenaho had 13 minutes of ice time.[8] He scored his first goal in the SM-liiga on October 29, 2022, in a 4–3 loss to KooKoo. He recorded 2 goals and a plus-minus of +3, and was named the third star of the match.[9] He finished the season with 21 points in 51 games, plus 4 points in 8 playoff games. On July 29, 2023, Hämeenaho was selected 58th overall by the New Jersey Devils in the 2023 NHL Entry Draft.[3][10]
Hämeenaho began the 2023–24 season on a hot streak, leading Ässät with nine goals and 14 points in the first 18 games.[11] Slowing down somewhat over the rest of the year, he finished with 14 goals and 31 points in 45 games, and Ässät missed the playoffs by just two points.[12] Joining Ässät's under-20 team for their playoffs, Hämeenaho recorded 12 points in 6 games en route to a championship victory.[13]
He won a bronze medal with Finland at the 2022 IIHF World U18 Championships. In a game against Sweden, he was chosen as Finland's best player of the game.[2]
Hämeenaho rejoined the Finnish WJC squad the following year.[15] He scored four goals and six points, including two goals in the bronze medal match where Finland conceded six straight goals, blowing a 5–2 lead to lose 8–5.[16]
Personal life
Hämeenaho's brother, Veikka, also plays in the Ässät organization, on the U20 team as of the 2023-24 season.[17] Hämeenaho's father, Jarmo, represented Kajaanin Hokki in the Mestis and has been a coach for Hokki and Ässät's junior teams.[6][18][19]