Elmer, 25, most recently played for FC Winterthur of the Swiss Challenge League (second division), where he started in all 21 matches he featured for the club, adding one goal. Elmer spent time at Swiss club Grasshopper Club Zürich during his youth career before joining Jose Mourinho at Chelsea F.C. in 2005. At Chelsea he played regularly for the reserve and youth teams during two seasons with the club.
Elmer left to sign for Swiss club, FC Aarau in 2007 and made 81 appearances for the club over three seasons. He joined FC Sion of the Swiss Super League in 2010. While at FC Sion he made 23 appearances for the first team and spent time on loan during the 2012 season with AC Bellinzona of the Swiss Challenge League. He signed with FC Winterthur midway through the 2012-13 season.
Elmer has represented his native Switzerland, earning eight caps at the U-21 level.