The 21-year-old is at Anderlecht in Belgium on a season long loan deal, having left in the summer.
The England youth international was hoping to get senior game time at the club, but it was not meant to be.
Speaking to the Daily Echo, Martin stated: "We've had different people go over and watch him, Matt Gill's been over, Olly Lancashire's (head of player strategy) been over.
"Gilly went over again last weekend to watch him. We are in constant contact, he's doing well and it's been good for him.”
"He's in a different environment and has a different challenge. He seems to be enjoying it. I would implore Sam to be better at text messaging and give us a bit more detail," Martin added jokingly.
"We will keep sending people over there a bit regularly to make sure we're having a conversation.
"Face-to-face contact is always better and easier. I wish I had the time to go over myself, but at the minute I haven't.
"There will be a time when I do. He's an important player for us in terms of the big picture. I think this season will be really good for him."