A member of Paddy McCarthy’s Under-23s squad, Thiselton (above left) featured regularly in the Under-18s side that challenged for the league title last season.
He joins top of the league Farnborough as they look to cement automatic promotion from the Southern Premier League South – they currently sit six points clear at the top of the table.
The young defender said: “I’m excited to get some experience of senior football under my belt at Farnborough. I’d like to thank the coaches at Crystal Palace for preparing me for this opportunity, and I look forward to getting started and learning as much as possible.”