Carelse has been training with Ajax in their pre-season preparations after revealing to KickOff.com last month that he was not interested in renewing his contract with Usuthu.
The 27-year-old was part of the Ajax squad that played in the Kimberley Invitation after proving his qualities in earlier friendly games.
Carelse confirmed to KickOff.com that he had signed for Ajax after a week of training.
Carelse went through a frustrating spell at AmaZulu last season, struggling with injury before being sidelined after his recovery.
The previous season the Alberton-born defender had captained the team to survival via the dreaded play-offs.
Carelse made his PSL debut in 2002 at Kaizer Chiefs after joining from Sporting FC, but then quickly moved to Dynamos where he established himself.
Carelse has been assigned to a central defence position, where he is expected to partner Brazilian Eduardo Ferreira.
Bageta’s move to Maritzburg is close to confirmation with Ajax boss John Comitis expected to give his blessings to the offer that has been tabled by the PSL returnees.
Bageta, meanwhile, continues to train with Ajax while awaiting Comitis’ return from abroad.