Arsene Wenger Arsenal
“They could have sold him last week but it opens at least the opportunity [to question] the dates of this transfer window.” - Arsene WengerReuters

Arsenal's chances of bringing in Diego Costa during the January transfer window strengthened with bookmakers slashing the odds on the Atletico Madrid striker moving to the Emirates.

The Gunners have been heavily linked with a switch for Costa, and Arsene Wenger only added fuel to the fire by admitting Theo Walcott's injury has further increased his intent over signing a new striker in the winter window.

"[Walcott's injury] has accelerated speculation first and of course my desire as well -- but let's not forget about Serge Gnabry who can play in the first team," Wenger told Arsenal Player.

"We have [Alex] Oxlade-Chamberlain back and we have many other players who can play on the flanks so to find better solutions than what we have internally will not be easy.

"Up front we lose Theo as a potential centre forward and that's maybe where we have to look outside. But we hopefully have [Nicklas] Bendtner back in three weeks. We are there for the opportunities but it's very difficult at the moment."

The January transfer window is a notoriously difficult time to bring in big names, with high-quality players already well and truly settled with their respective clubs and looking to kick on during the second half of the season.

However, that has not stopped the bookies from bringing down Arsenal's odds over Costa from 8/1 to 2/1, according to the Daily Star. The Gunners, at the moment, are clearly ahead of the other two Premier League clubs linked with the Brazil-born Spanish striker, with Chelsea at 8/1 and Manchester United further behind on 9/1.

Odds came considerably down when bookies received huge bets on a Luis Suarez move to Arsenal in the summer. While the transfer eventually failed to materialise, there was a lot of truth to the rumour in the end with Arsenal failing with a now infamous £40 million and £1 bid.

Costa has a release clause of €38 million (£31.3 million), with some recent reports suggesting it will become active only during next summer.

However, Atletico Madrid sporting director Jose Luis Perez Caminero earlier this week confirmed the release clause, but insisted the striker was going nowhere during January.

"The player has a clause of €38 million and the big clubs in England know this," he was quoted as saying by Marca. "Diego Costa has matured and is smart when it comes to decision making.

"Right now, Costa does not think of leaving, he is hooked on Atletico. He has re-signed a deal that is important, I am confident he will continue with us."