A person who is filled with deception and dishonesty. A person who mis represents their intentions.

A person that plays games, like mind games with others

Someone who is willing to stick with a team even when things look down.

1. descriptive noun / adj.

A term used by Sport-literature individuals to describe a sportsman that can be relied upon to deliver and succeed at the crucial, definining and pivotal moments in his teams' , or his own sporting conquests.

It is most commonly used in Footballing terms - a big game player is someone who can deliver goals, or play well and do his role effectively and inspirationally - and not be over-awed, but create fear and awe in the opposition, without getting swayed in by the occasion , be it a crucial fixture against a big team, or a World Cup Final , or Cup Tie and other such engagements. People say that a great player can be defined most by their ability to be big game players - delivering against the biggest teams, when their teams need it the most, and succeeding against all qualities of opposition.

This term can also be called as 'Big Match Man'.

This term although is mainly attached to Football, it can be attached to other sports as well.

A "game player s" is a person who desperately tries to destroy a message board. More specifically, message boards related to video games.
A "game player s" has been said to love video games, but hates anyone else who gets near them.

Another way of saying don't blame me; this is how the system works.

Ex 1:
If the game is forced on the individuals required to "play" it... Such as war or an area in conflict etc. Using tactics to win or survive may not always be fair or morally right. In this instance, hating the player is useless and the quotes logic seems to ring true. This also covers situations where the rules say you can do certain things, the rules are followed and the other players just don't like that you are able or competent at taking advantage of and succeeding at the game.
However...
Ex 2:
If the game is not forced, there is no situation requiring life threatening survival choices or there was not agreement to start a game with certain parameters .. This saying is used to absolve someone of the act of wrong doing to another by convincing either or both the perpetrator and victim that there was no other choice. Fairness, rules , laws and social norms seem to get lumped into this version of the definition and it's implied that the victim is wrong for holding the perpetrator responsible for their actions. More specifically, calling life a game and using this quote to avoid responsibility for being unfair, deceitful or cheating on purpose and existing outside laws, rules and social norms.