QPR boss Mark Hughes insists the club are doing all they can to keep their players safe on the pitch.
Bolton midfielder Fabrice Muamba is still critically ill in hospital after suffering a heart attack in Saturday's FA Cup tie at Spurs.
Hughes admits the mood at QPR's Harlington training base was 'flat' after returning to training this morning following the incident at White Hart Lane.
But he says everyone at the club receives regular checks to ensure they are fit and healthy.
"I checked our policy in terms of screening and every young player is screened, every player that comes into the club is screened as a matter of course,” said Hughes.
"If there's anything more that can be done, I'm sure that will be implemented.
"But, at this moment in time, I don't think as a club we can do any more. I'm sure that's the case for many clubs.
"These things can happen irrespective of any screening processes that you have and that's the frightening thing about it.
"It can strike down anybody. These are fit young men and that's why it's so shocking.
"You feel it should never happen because of the level of fitness that these guys have.
"But, unfortunately, it does."
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