Kenny Dalglish claims he is fully satisfied with Liverpool's medical procedures after the collapse of Bolton midfielder Fabrice Muamba last weekend.
Muamba showed further encouraging signs in his recovery from a cardiac arrest two days after the FA Cup tie at Tottenham that has prompted the Premier League to investigate whether improvements can be made to their medical tests.
But the Scot revealed that some conditions may be virtually undetectable and believes the 23-year-old Trotters star, who fled to England from Congo's civil war in 1999, has been 'unfortunate'.
"We are happy with what we do for the players," said Dalglish.
"Our players are scanned every two years and someone coming to the club on a transfer or a young boy at 17 is scanned immediately.
"I don't know how accurate the scanning is for everyone; Fabrice was also scanned - I'm led to believe four times - but you are not going to pick everything up and maybe he's been a little bit unfortunate.
"The encouraging thing is there has been positive news coming out, but he has a long way to go and he still needs the help and support and prayers of everyone in the footballing world to help him get over this.
"It is encouraging for him but we have to be cautiously optimistic because I think there are going to be ups and downs for the boy.
"But most importantly he is moving in the right direction and is progressing but I think it will be slow."