Jonathan Davies
Jonathan Davies is a regular fixture for Wales and scored one try during the recent Six Nations tournamentGetty Images

Wales has been dealt a significant blow ahead of the 2015 Rugby World Cup with the news that Jonathan Davies is set to miss the entire tournament due to a knee injury.

The Clermont Auvergne centre, who started alongside Jamie Roberts for his country in all five of its Six Nations matches earlier this year, ruptured an anterior cruciate ligament during the recent 29-17 Top 14 victory at Montpellier.

Such a serious injury is expected to leave Davies sidelined for a minimum of six months, meaning he will have virtually no chance of recovering in time for the tournament that begins in mid-September and ends with a final at Twickenham on 31 October.

"WALES SQUAD UPDATE: @JonFoxDavies will miss the @rugbyworldcup after rupturing his anterior cruciate ligament," the Welsh Rugby Union (WRU) announced via their official Twitter account.

Warren Gatland's Wales has warm-up tests against Ireland and Italy to come before it begins its World Cup campaign against Uruguay in Cardiff on 20 September.

An eagerly anticipated clash with England takes place six days later, and they will then face Fiji and Australia in a bid to escape a notably difficult Pool A.

One of South Africa, Samoa or Scotland are likely to await it in the quarter-finals should Wales progress that far.

Elsewhere in rugby, hooker Dylan Hartley is in hot water once again after being cited for an alleged headbutt on England rival Jamie George during Northampton Saints' 24-29 loss to Saracens in the Aviva Premiership semi-final clash at Franklin's Gardens on 23 May.

England Head Coach Stuart Lancaster has previously sought to remind the New Zealand-born 29-year-old of the need to maintain strict discipline after he was handed a three-week suspension in December for an elbow on Leicester Tigers back Matt Smith.

Hartley, banned for 11 weeks in 2013 after being sent off in the Premiership final for swearing at referee Wayne Barnes, will go up before a three-man RFU disciplinary panel this week and it remains to be seen if this latest controversy will impact upon his chances of selection for the World Cup.

Twitter/@WelshRugbyUnion