It's very simple really but there are so many variations of similar types. The following will sound like a muddle most likely, so you will have to fathom it out.
Pre Match: 90% of the time, I use assertive and whatever "relax" type talk is available, they sometimes differ. If there isn't a relax available and it is replaced by an "enjoy" type, I will often do "expect to win" for home games against lesser opposition and for away games or tight home games, "for the fans". Again, all are done assertive.
Half Time: If winning by any scoreline, I use the assertive "doing well, keep it up lads" or similar. If drawing against lesser opposition, assertive "far from pleased" and if against closer opposition I'll either do assertive "for the fans" or "doing well, keep it up" in away games of these type.
Post Match: Again, all assertive. If won, "very pleased" or similar. If drawn or lost, it all depends on the opposition. For lesser opposition, "not happy" or similar, if at home to similar opposition then the same but if away to similar/better opposition then user "unlucky" or similar.
Cheers for that bud, update me at the end of your season