A product of local Kuopion Palloseura (KuPS), Pennanen made his senior début on 29 April 2007, aged 16, against VIFK. A month later, he was a starter against PK-35. That season he appeared in 13 first-team matches. In February 2009 Pennanen signed a two-year contract with the Dutch team Twente along with teammate Tuomas Rannankari.
After not making a single appearance for the Twente's first-team, Pennanen left the Dutch champions during winter 2011 and signed with TPS.[1] He signed with RoPS before the 2014 season.[2]
On 14 December 2021, he signed a three-year contract with Ilves.[6]
On 23 July 2023, Indian Super League club Hyderabad announced the signing of Pennanen on a one-year deal.[7] In February 2024, Pennanen terminated his contract with Hyderabad due to unpaid salaries.[8]
On 28 February 2024, Pennanen returned to Finland and Kuopio after signing a one-year deal with his hometown club KuPS, with an option to extend for one more, reuniting with his former coach Jani Honkavaara.[9] On 24 July, his deal was extended for the 2025.[10] On 21 September, Pennanen helped his team to win the 2024 Finnish Cup title by scoring a brace in the final in a 2–1 win against Inter Turku. On 19 October, Pennanen scored the winning goal in the last match of the season against HJK Helsinki, helping his side secure the Veikkausliiga championship title and completing the club's first-ever double.
Career statistics
Club
As of match played 19 October 2024
Appearances and goals by club, season and competition