Ketelaer terminates Foals contract
The 26-year-old agreed to the termination after being left out of the first-team squad by coach Holger Fach this term.
He has reportedly already agreed a deal with Bundesliga Zwei promotion challengers Nurnberg, but will only join the club officially in the summer.
Ketelaer, who was born a stone's throw from the Bokelberg Stadion, hit the headlines as a youngster before leaving the Foals for Hamburg in 2000.
After failing to settle in Hamburg, however, he returned to Gladbach last season and played an important role in helping keep the club in the top flight under coach Ewald Lienen.