Blackburn have signed defender Doneil Henry on a month's loan from West Ham.
Miles Addison has joined Blackpool on a month's loan from Bournemouth.
The former Colombia international, now 42, is fondly remembered by fans on Tyneside after a two-year spell as a player with the club in the 1990s which was most notable for a hat-trick in a 3-2 Champions League win over Barcelona.
He told the Sun: "A year ago I spoke with Newcastle's owners about bringing over players from my coaching school (in Colombia). It didn't happen due to some requirements of the English league but then, during informal meetings with fans, I said I'd be interested in returning.
"That encouraged the owners and three months ago they invited me over.
"I'm motivated and like the city. I often accompany the team when they are travelling in England.
"It is a significant opportunity and hopefully something will materialise."