Johnny Sexton takes part in training but news is not so good for Keith Earls

Johnny Sexton is up and running but doubts still surround his involvement in Sunday's World Cup quarter-final with Argentina.

Centre Keith Earls is also a doubt after sitting out training today in Cardiff, with speculation surrounding his fitness as Ireland delay calling up a replacement for Jared Payne. Sexton was replaced by Ian Madigan during the first half of last weekend's 24-9 win over France after shipping a couple of heavy tackles. Subsequent scans on his groin have detected no major issues and the Ireland fly-half undertook some non-contact training today. “Johnny did about three and a half kilometers running,” said scrum coach Greg Feek. “That’s a positive so we’re quietly confident. We’ll see how he goes again on Friday.” There was less information on Munster man Earls, who appeared to suffer an arm injury during the second half of the bruising encounter with Les Bleus. “We’re just going to see how he goes. We’re looking after him a bit and it’s not too bad so we’ll see how he goes on Friday as well," said Feek. “He’s just a bit battered. It’s nothing too major. It’s just, at this stage, you want to do the best you can to get everyone fit and available.” Rhys Ruddock and Mike McCarthy both trained with the squad after being called up to replace Peter O'Mahony and Paul O'Connell respectively. Friday's session will be the last chance for head coach Joe Schmidt to assess his injury-hit squad as the players have a day off on Thursday.