Simplify the following text for a Grade 5 native English-speaking person.
Original: Dieter MÃ 1\/4 ller ( born Dieter Kaster on 1 April 1954 ) is a former German footballer , who is currently the chairman of Kickers Offenbach .
Simplified: Dieter MÃ 1\/4 ller ( born 1 April , 1954 ) is a former German football player .