German Formula One racing champ Heinz-Harald Frentzen has announced his retirement, ending a career which began in 1994 and consisted of three grand prix victories. Frentzen has been released by his racing team Sauber. For most of his career in F1, Frentzen has had to contend with life in the shadow of compatriots Michael and Ralf Schumacher despite consistent driving which led to his best result -- the runners-up position in the 1997 Drivers' World Championship. Sauber’s decision to release the German left the 36-year-old without a drive, and with only Jordan and Minardi still having seats available, Frentzen has opted to end his F1 career. However, he will not be leaving motor racing altogether. According to reports in the German press, Frentzen intends to return to the touring car circuit next season.