Theo Walcott receiving treatment at the Emirates on Saturday.

Arsenal manager Arsene Wenger will have the full backing of majority owner Stan Kroenke and the board should he wish to make any major moves in the January transfer window following the loss of England forward Theo Walcott for the rest of the season with a knee injury.

The Gunners confirmed their worst fears late on Monday following tests and specialist consultations, which revealed the 24-year-old would need surgery following anterior cruciate ligament damage sustained when making a defensive tackle during the closing stages of the third-round FA Cup win over Tottenham at the Emirates Stadium.

The club have rallied behind Walcott, who is expected to undergo an operation next week once the swelling on his left knee has eased, with messages of support flooding in from fans and fellow professionals alike.

Wenger, though, must immediately turn his attention on how to accommodate for the loss of Walcott, who was a potent weapon in the Arsenal attack and had netted five goals since his return from a stomach injury.

Forward options for the Premier League leaders were already depleted, as Nicklas Bendtner will need more weeks to fully recover from the ankle injury he picked up while scoring a late goal in the 2-0 win over Cardiff on New Year’s Day while France Under-21 international Yaya Sanogo, a free summer signing, has only now stepped up his rehabilitation from a back problem.

Frenchman Olivier Giroud missed the Spurs match because of illness after shaking off a minor ankle injury, and remains Arsenal’s lead attacker.

While the loss of Walcott is clearly a blow, the emergence of German 18-year-old Serge Gnabry, who set up the opening goal against Spurs, and imminent return to full fitness of Alex Oxlade-Chamberlain at least give Wenger some ready-made cover on the right side.

However, how best to offer direct support to Giroud will now be key for Wenger as Arsenal look to last the distance in the race for honours through to May.

Fit-again Lukas Podolski offers another option, although the German striker was somewhat subdued when deployed in a central role against Cardiff, while club-record signing Mesut Ozil can provide telling back-up behind the main forward.

Although Wenger concedes a big-money signing during January is notoriously difficult to push through, reports said American owner Kroenke and the rest of the Emirates Stadium board would sanction raiding some of the club’s substantial cash reserves should the manager identify the right calibre of player.

Atletico Madrid frontman Diego Costa certainly fits that bill having impressed in La Liga, but would also come with a hefty £32m-plus price tag even if the Spanish club were to consider selling, which appears unlikely.

Although Wenger appeared to play down the possibility, veteran Fulham forward Dimitar Berbatov would provide a cut-price short-term solution, with the former Tottenham and Manchester United man likely to be available for under £5m if the Cottagers were open to offers.

Lazio veteran Miroslav Klose, 35, would also provide the experienced cover required for the Gunners, with the German international forward out of contract in the summer.

Promising Alvaro Morata is an-other stop-gap loan option, al-though Real Madrid have always maintained a reluctance to let him leave despite limited current first-team opportunities.