Wales captain Ryan Jones was ruled out of the remainder of the British and Irish Lions tour of South Africa on Friday just a day after joining the team as an injury replacement.

Jones was called up as cover for injured flanker Stephen Ferris, but neurological tests showed he was not in a fit state to play.

"I am very disappointed that on medical grounds I have been told that I am not currently fit enough to play an active role on the tour," Jones said in a statement.

Jones underwent the same medical tests as all the Lions squad on his arrival but a further test by a neurosurgeon was sought and he recommended Jones did not play for three weeks after suffering two blows to the head during Wales's tour of North America.

"On the advice of the neurosurgeon it was determined that it was not safe for Ryan Jones to undertake any physical contact for a mandatory three weeks. This is in line with IRB Regulation 10.1 on concussion," the statement said.

Jones became the third player to be ruled out of the tour this week after the withdrawals of Ferris and Welsh winger Leigh Halfpenny.

"I was looking forward to getting involved with the rest of the lads but I guess it wasn't meant to be," the 28-year-old Jones said.

"I feel okay at present but obviously I have to listen to the neurosurgeon's advice in terms of my health, and to ensure I make a full recovery," he added.

Jones won three caps for the Lions in New Zealand in 2005 and has played in 33 tests for his country.

Head coach Ian McGeechan will not be seeking a further replacement.

(Writing by Jason Humphries; editing by Kevin Fylan)