Ireland’s Stephen Ferris has been ruled out of the remainder of the Lions Tour after sustaining medial ligament damage in his knee during training yesterday. The flanker, who has excelled so far in South Africa, will be replaced by Wales captain Ryan Jones. The Ulster flanker scored twice on tour already and looked a frontrunner for a Test spot against the Springboks.

A scan on his twisted knee this morning, however, revealed ligament damage that has a recovery time of between four and six weeks.

Ferris is the third Irish player selected in the initial squad to have to pull out because of injury, after Tomás O’Leary and Jerry Flannery were ruled out before the tour even began.

"Ryan Jones has been called up to replace Stephen Ferris who unfortunately sustained a knee injury during Monday afternoon's training,” said head coach Ian McGeechan today.

“He twisted his right knee in a training drill and following a medical assessment it was decided that he should undergo a scan to determine the extent of the injury."

"He had the scan on Tuesday morning that showed he had a grade two tear to his medial collateral ligament. This usually requires a four to six week recovery period and is severe enough to mean he will miss the rest of the tour.

“Therefore with six matches left on tour after Wednesday's match against the Sharks we believe we need to fly out a replacement as cover for the backrow."

Jones is on the reserve list and ahs been playing for Wales on the tour of north America over the last few weeks.

“He will fit right in as he knows a lot of the players and of course he was a Lions replacement on the 2005 tour to New Zealand,” added McGeechan. “In fact, on that tour he showed how competitive he is as an individual by forcing his way into the Test side for all thee matches against the All Blacks."

Jones will arrive on Thursday and link up with the squad in Cape Town. Considering he is match fit, he may well feature in Saturday’s game against Western Province.

There is also concern within the camp over Wales international Leigh Halfpenny, who arrived late in South Africa after remaining at home for intensive treatment on a thigh injury.

The Cardiff Blues wing made his first tour start against the Cheetahs last Saturday.

"He has aggravated his old injury," said Lions assistant coach Shaun Edwards, who confirmed Halfpenny would also be scanned. "He recovered very quickly from the last time. It is nowhere near as bad as that, so we will wait and see. Scans are amazing things nowadays, so we will wait to see what that says.

"He was doing some extra training at the end of a session, practising his kicking, and he just felt it strain up a little bit."

The Lions will tackle a Sharks team shorn of Test stars like John Smit, JP Pietersen, Ruan Pienaar and Adi Jacobs, who are currently in camp with the Springboks.

And, while the they can still expect a fierce battle from South Africa's second-ranked Super 14 side - their line-up features Springboks such as Deon Carstens, Johann Muller and Jannie du Plessis - Sharks coach John Plumtree believes the absence of so many top names is unfortunate.

"Personally, I think the (South African) provinces should be at full strength," said former Swansea boss Plumtree, who coached Wellington against the 2005 Lions. "A tour like this is unique and there should be less emphasis on just winning Test matches, more a celebration of rugby.

"It's a pity we don't have a full-strength Sharks tomorrow.

"It is not a criticism, it's just a real pity. It seems to be the way of the modern Lions tour."

If the Lions are to make it four wins out of four - they've never lost in 10 previous meetings stretching back 99 years - then breakdown supremacy and vastly-reduced turnovers will be vital.

"The breakdown and what goes on at the ruck in terms of quick ball is the most important part of the game," admitted Lions skipper Paul O'Connell. "We've been working on it and we will continue to work on it right up until the end of the tour.

"With three games to go, we are halfway through the build-up before the first Test and probably places are still up for grabs.

"The more I think the squad believes that and the more it continues that way, the happier the squad will be."

Sharks: S Terblanche; C Jordaan, A Strauss, R Swanepoel, L Vulindlu; M Dumond, R Kockott; D Carstens, S Badenhorst, J du Plessis, S Sykes, J Muller (capt), J Botes, J Deysel, K Daniel.

Replacements: C Burden, P Cilliers, A van den Berg, M Rhodes, C McLeod, G Cronje, L Mvovo.