Eastham is set to go into Cheltenham's squad to face the Mariners on Saturday and Robins' manager Mark Yates was delighted with his acquisition.
"I've been actively searching for another young centre-back with some pace, power and strength," Yates told the club's official website.
"Ash has got that, he's one we know, he can slot straight back in and he's a good character.
"Hopefully we can keep hold of him for a bit and help to develop him as a player so that he can keep on improving."
Source: Team Talk
Source: Team Talk