Arsenal and England forward, Theo Walcott, must undergo surgery on a serious knee injury and faces at least six months on the sidelines, which rules him out of the 2014 World Cup showpiece.

Arsenal confirmed on their website that Walcott suffered a 'ruptured anterior cruciate ligament' injury to his left knee during their FA Cup victory over Tottenham on Saturday.

The Gunners confirmed their speedy forward will undergo surgery in London in the near future, but is set to miss the remainder of the season as well as the World Cup in Brazil.

The seriousness of the injury is shock for Arsene Wenger and his side, particularly since the injury didn’t appear this serious when Walcott left the field on a stretcher and even signalled “2-0” to the Tottenham fans - a gesture which will not be charged by the FA.

Wenger had originally hoped Walcott would only miss a maximum of four weeks, but now has to replace the in-form player until the end of the season.

Walcott had just started to find his best form following a two month lay-off with an abdominal injury.

He regained his spot in the starting XI against Man City and has since scored five goals in six starts.

The England international was leading Arsenal’s line against Tottenham after Olivier Giroud and Nicklas Bendtner had already been ruled out with injuries and the injury is a massive blow for Arsenal’s title chances.

It is yet to be seen whether Arsene Wenger will become active in the January transfer window to bring a new striker to the Emirates Stadium.

Does the Walcott injury mean Arsene Wenger need to become active in the transfer market, and who can the Gunners buy? Have your say in the comment section below.