While football is an odd and peculiar world where breach of contract is not infrequent but generally the industry settles the issue by paying up players contracts so there is no financial loss, in the absence of loss there is little or no point for players to sue for breach.
This is different Derby have breached the contract by offering Keogh reduced terms and then terminated the contract by reason of gross misconduct. In isolation they have a solid case. Firstly the incident occurred following a club sponsored evening out so it is deemed to be in the work place. Secondly Keogh's actions could be deemed to be reckless and the consequences have resulted in the contract being frustrated through his injury. Thirdly Derby could also argue that his actions damaged the reputation of the club.
Completely agree they appear to have made a huge mess of it, which is incredible considering they have surely taken this action under advisement.
As for offering a lower contract, then sacking him. If there is any evidence of that whatsoever, then surely that enters the realms of blackmail.
In respect of the above two points you made though, I suspect breach of contract and what a normal person would find is gross misconduct is even more frequent than we know and in fact the usual action is to ignore, overlook or punish through a fine rather than contract termination.
I also disagree that in isolation they would have had a solid case. The club took the players to an event which involving alcohol, the fact he stayed out and had "too much" I don't think in itself would be gross misconduct, not without another action which caused embarrassment to his employer. His accident has embarrassed his employer but only because of the actions of others, which may be too remote to sack Keogh for.
