Arsenal Alexis Sanchez
Alexis Sanchez's form will be crucial if Arsenal want to progress in the leagueGetty Images

Arsene Wenger has revealed that he has no idea why Alexis Sanchez chose Arsenal over Liverpool in the summer in spite of the Reds being embroiled in a transfer battle with Barcelona over Luis Suarez.

It would have been easier for the Catalan club to allow Sanchez to move to Anfield in a part exchange for Suarez, but the Chilean put his hand down in negotiations and forced a move to north London, where he has been a revelation thus far.

The South American has scored 19 goals thus far this season, including 13 in the league and was literally carrying the Arsenal team on his shoulders in the first half of the season.

His influence has diminished over the turn of the year with the player struggling to cope with the rigours of the Premier League but his influence is such that the Frenchman is forced to play him in every game, irrespective of his physical state.

Sanchez is expected to play a critical role if the Gunners have to take anything against Liverpool when the two sides meet at the Emirates on Saturday, in a game that can make or break the Reds' hopes of securing a Champions League spot.

"At the end of the day, only Sanchez can explain to you why he has chosen us. I don't know why he did that, but we are happy that he made that decision," said Wenger.

"I was [aware of Liverpool's interest], but you never know if it is really true, but I thought it could be because of the interest in Suarez [from Barcelona].

"In the negotiations, yes, it is a strength -- and it makes sense, an exchange and some money for Liverpool.

"If you look at the qualities, efficiency, work-rate, fighting spirit -- [he is at the] top. When [the game] becomes flat, he can revitalise the strengths and dynamics of the team and the supporters," the Frenchman added.

Meanwhile, the Gunners are in the process of riling Liverpool yet again, with their reported interest in Raheem Sterling, who is flattered by the Gunners' interest in his services.