During his playing career, Jalonen appeared in two SM-liiga games for JyP HT in the 1985–86 season. He also played for JYP, Jääahmat and Lohi in lower divisions.
Coaching career
Jalonen started his coaching career with SM-Liiga sides, managing Ilves from 1992 to 1995, and Lukko during the 1996–97 season. Afterwards, he took over Mestis side Vaasan Sport for the 1997–98 season. After a one-year stint with Sport, Jalonen spent three seasons abroad. First, he coached HC Alleghe in Italy and then two seasons in the United Kingdom, with the Newcastle RiverKings and Newcastle Jesters in the British Ice Hockey Superleague, respectively. For the 2001–02 season, Jalonen returned to Finland and signed with HPK. He went on to spend six seasons with HPK, and led the team to remarkable success with placing third in the SM-liiga in 2001–02, 2002–03 and 2004–05. His era in Hämeenlinna reached a climax in 2005–06, when he led HPK to win the first Kanada-malja in the franchise history. The same year, he was awarded with the Kalevi Numminen trophy for being the best coach in the league. In his last season with HPK in 2006–07, Jalonen added yet another SM-liiga bronze medal to his record. After his years in HPK, Jalonen started coaching the Finnish national team, first in the role of an assistant coach under Doug Shedden in 2007–08, and then as the head coach from 2008-09 onward. In 2010, Jalonen's team won the Olympic bronze medal in Vancouver, and in 2011 he coached the Finnish national team to the nation's all-time second World Championship title. In the final game, Finland beat arch rivals Sweden with a score 6–1. While Jalonen remained as the head coach of the national team until the end of 2012–13 season, the national team failed to win additional medals under his tenure. During the 2012–13 season Jalonen signed with KHL side SKA St. Petersburg, replacing Milos Riha during the season. He went on to lead the team to conference finals in the Gagarin Cup. He stayed with SKA the following season, 2013–14, but the team's run ended in a loss in conference semi-finals. For the 2016 World Juniors that were organised in Finland, Jalonen was hired to coach the Finnish U20 team. He successfully coached the Finnish team to World Junior Championship on home ice, beating Russia with a score 4-3 in the final at Hartwall Arena. In the 2016–17 season, Jalonen returned to the KHL with the Jokerit. Jokerit made the playoffs but were knocked out in the first round of the Gagarin Cup. In 2017 Jalonen was re-elected Finnish national team as head coach to replace Lauri Marjamäki after the 2018 World Championship. The contract originally covered the seasons 2018-2019 and 2019–2020, and was later extended by another three years to include the 2021–2022 season.
