Mthembu was said to be on the verge of extending his stay at the Bethlehem based side when he suddenly signed with City.
The Belgian mentor expressed his unhappiness at losing Mthembu whom he claimed to have polished into a fine player he is now after the former Kaizer Chiefs and Orlando Pirates striker had struggled to make any impact in previous seasons.
“We lost Mthembu who was a hard worker. We worked on him and made him better but now he has stabbed us in the back but I understand that is how football works,” said Eymael.
He said he would be asking Stars for some money so he can get another striker as his current ones are misfiring.
“I think Eleazar (Rodgers) can give us something. Once he scores the first goal it will help with his confidence. But I will speak to the chairman again because I want to bring another player,” said Eymael.