Warren Gatland
Warren Gatland is unsure why Wales have received an official warning from World Rugby over the use of extra players in training AFP

Warren Gatland claims Wales have not broken any rules relating to the participation of additional players not named in their 31-man World Cup contingent during an open training session at London Irish's Hazelwood Training Centre in Sunbury. Although no breach was intended, World Rugby have subsequently issued the Welsh Rugby Union (WRU) with an official warning and provided a reminder that players from the extended squad and even potential injury replacements are not permitted to be involved.

Nicky Smith, Rob Evans, Rhys Patchell, Jordan Williams, Dan Baker, Kristian Dacey, Dan Fish and Aled Summerhill were the players who supposedly took part in the session, which came just three days before Wales continue their Pool A campaign with a heavyweight clash against old rivals and hosts England at Twickenham. Despite the warning, however, Gatland claims the 2011 semi-finalists have done nothing wrong and expressed confusion over how the incident had been dealt with.

"I'm sure you've all read the statement," he said at a press conference on 24 September as quoted by Wales Online. "We haven't broken any rules. According to World Rugby we've broken the spirit of the rules so I don't know what that means.

"We haven't done anything underhand and I don't know what we've done wrong. You've either got rules or no rules so what does spirit of the rules mean? It's either in the rules or not. If we we're going to sneak players in we wouldn't do it at an open training session. Go and ask World Rugby what rule was broken."

Gatland has made nine changes to the side that beat minnows Uruguay on home soil last weekend, with experienced bodies such as Jamie Roberts, George North, Alun Wyn Jones, Bradley Davies, Gethin Jenkins and Taulupe Faletau all back in the starting XV. Dan Lydiate and Liam Williams also play despite suffering head and thigh injuries respectively at the Millennium Stadium, while Scott Baldwin and Tomas Francis feature in the front row. Hallam Amos retains his place ahead of British and Irish Lions wing Alex Cuthbert.

England have only made three alterations to the side that recorded a nervy 35-11 win over Fiji on the tournament's opening night, but the style of their team has been changed significantly. With Jonathan Joseph ruled out with a chest injury, head coach Stuart Lancaster has moved Brad Barritt to outside centre and handed Sam Burgess just a second international start in rugby union, as well as dropping first-choice fly-half George Ford in favour of the more robust Owen Farrell. Billy Vunipola is also in at number eight in place of Ben Morgan, with the Gloucester man suffering with a knee issue.

Sam Burgess
Sam Burgess has only played one season in rugby union since joining Bath from the South Sydney Rabbitohs last year Getty

Many have suggested that England's choice to revert to a more defensive midfield trio for such an important fixture will lead to a chronic absence of attacking flair that could prove costly to the outcome of the so-called 'Pool of Death', which also includes Australia. While Gatland admitted he was surprised by the selection, he dismissed the notion that Lancaster's side would be diminished by the likes of Burgess.

"Sam Burgess is a world-class player," he said. "We're just really excited about Saturday. England are a quality team with a huge amount of strength in depth. We were expecting England to go with the same 10,12,13 so that threw us for a few days but there's clearly a few leaks there. Sam is similar in size and stature to Jamie Roberts and Brad Barritt is a very experienced defender. They've got some world-class players."

Lancaster himself has denied that his decision to dispense of Ford is a sign of panic, although he is likely to come under significant pressure if it backfires. James Haskell and Alex Goode have been included among the list of replacements for the match.

More about Rugby World Cup 2015