The Mexican has 18 months left to run on a deal which has seen the player loaned out to both Cruz Azul and Necaxca in his homeland with limited success.
Pena retweeted a picture of himself with a member of the public at Glasgow’s George Square. He also shared a picture online with teammates, Alfredo Morelos and Daniel Candeias.
After making only 6 starts for Rangers in his first spell, Pena was loaned out to former boss Pedro Caixinha at Cruz Azul, but fell foul of the club after a number of off-field incidents.
Necaxa decided to take over Pena’s loan but his stay was cut short after the club decided to terminate the loan two months early.
The midfielder is due to report for training at Rangers in January.