He told the South Wales Evening Post: "I've talked to Marvin about how I feel going forward.
"I like him, but he needs to improve on a lot of things - his fitness for one.
"It is a case of the club speaking to his representative and seeing what happens.
"There's no definites here and there just yet but we will see in the coming weeks."
For the big stories and the banter follow us on Twitter: @tribalfootball