Donaldson has joined Tranmere on a one-month loan deal and manager les Parry was delighted with the signing of the youngster.
“I’m really pleased to be able to bring Ryan to the club,” said Parry.
“He’s a talented young player who I’ve watched a lot for Newcastle’s reserves and last season for Hartlepool and he’s always impressed me.
“He’s good on the ball and has an eye for goal and he’ll be an excellent addition to our squad. I’d like to thank Newcastle manager Alan Pardew for allowing Ryan to join us.”