Career
He spent the majority of his career with 1. Football Club Magdeburg playing in the Deutsche Demokratische Republik-Oberliga, East Germany"s top flight. Siersleben joined the 1.
Football Club Magdeburg youth team in 1974.
In 1978 he was nominated as a defender for the Nachwuchsoberliga (a youth competition) side. At age 18 he was made part of the Deutsche Demokratische Republik-Oberliga squad for the 1979-1980 Deutsche Demokratische Republik-Oberliga season, playing in his first match on 25 August 1979 as a leftback against BSG Chemie Leipzig.
During his first Oberliga season he played in ten matches. In the following season Siersleben played in the Nachwuchsoberliga exclusively, having begun studying for a Diplomsportlehrer degree in 1980.
Only in the 1983-1984 Deutsche Demokratische Republik-Oberliga season could he establish himself in the Oberliga squad, playing in 16 matches.
Siersleben played six matches on European level for 1. Football Club Magdeburg. He played in the return leg as well. From 1984 onwards Siersleben was an Oberliga regular, never playing in less than 20 matches per season until the end of the Deutsche Demokratische Republik-Oberliga in 1991.
After his club had missed out on qualifying for the 2nd Bundesliga in 1991, Siersleben spent three seasons in the then third-tier NOFV-Oberliga until 1994.
In this division he played in 98 league matches, no longer as a defender, but as a midfielder. In his final season with the club, Siersleben was made team captain.
After the Saxony-Anhalt Cup final against Hallescher Football Club, he ended his career with 1. Football Club Magdeburg. Aside from his 12 league goals, Siersleben scored twice in the national cup competitions.
When 1. Football Club Magdeburg did not qualify for the new Regionalliga Nordost in 1994, Siersleben followed former teammate Rolf Döbbelin who was now manager of Fortuna Magdeburg.
He stayed at Fortuna until 1999, leaving for lower league side MSV Börde where he ended his playing career in 2000. After ending his playing career, Siersleben took over the manager position at his last club MSV Börde. In 2003 he moved back to 1.
Football Club Magdeburg where he led the reserve team from the then eight-tier Stadtklasse to the then fifth-tier Verbandsliga within four years.
After internal differences he was let go in April 2008.