Surely you acquainted yourself with the rules of the game when you started playing? It didn't take long and I found the answer to your dilemma there. Two vital questions:
a) can I go into debt?;
b) if the answer to a) is 'yes', what happens when I do?
Both those questions are answered in several places, if you bother to look.
If you didn't read the rules, then you can garner little sympathy from this quarter as this is a situation you got yourself in, and didn't get out in time.
The rules say 'the best player(s)' - if they're not talking about the highest value then they're talking about the highest quality, which obviously meant your 155% player - why anyone would want to spend over £80 (UK) on a single player in a game is beyond me...