The Stockholm native began to turn heads with the Nacka HK squad in the second division and represented Sweden at the European Junior Championships in 1985 and 1986. He joined the prestigious Djurgardens IF club in 1986-87 and helped them win consecutive national titles in 1989 and 1990. Garpenlov also played on the Swedish squad that won the bronze medal at the 1987 World Junior Championships and competed at the 1988 tournament.

The clever forward was chosen 85th overall by the Detroit Red Wings in 1986. A few months after aiding Sweden's silver medal performance at the 1990 World Championships, Garpenlov made his NHL debut in Motown. He scored 40 points as a rookie then notched four goals to help his country win the gold medal at the 1991 World tourney.

The 1991-92 season proved to be eventful with an appearance at the 1991 Canada Cup and a trade that brought the talented winger to the San Jose Sharks. The trying year for Garpenlov was rescued by Sweden's second consecutive World Championship. Garpenlov scored 22 goals for the dreadful Sharks in 1992-93 then proved to be a valuable two-way performer when the club improved by leaps and bounds the next season. He and "OV " linemates Sergei Makarov and Igor Larionov helped the club come within a game of reaching the semifinals in 1994.

In March, 1995, the tricky winger was traded to the Florida Panthers for future considerations. In 1995-96 he scored a personal high 23 goals and was a part of the third year club's remarkable drive to the Stanley Cup final. Garpenlov battled injuries and was a decent utility player for the Panthers over the next three seasons. In June, 1999 he was claimed by the expansion Atlanta Thrashers and played a support role on the young club in its inaugural season. Prior to the 2000-01 campaign, Garpenlov brought his NHL tenure to an end and returned to Sweden to play for Djurgardens.