Mainz coach Achim Beierlorzer has explained holding back on-loan Liverpool striker Taiwo Awoniyi.
The Nigerian is set to return to Liverpool after the Reds' grew frustrated with the forward's loan with the Bundesliga club.
Speaking to Kicker, Beierlorzer hit out at the player's contribution for the club.
"He is a very young player who has athleticism, speed and a good shot, everything you need," he said.
"But you don't play because you have everything, but because you are effective, I have to make that clear."