Despite winning the game 2-1, the Gunners boss still expressed his surprise at some of the referee's decisions.

After a somewhat topsy-turvy campaign, Arsenal finished out 2014 with a crucial win over West Ham.

The Gunners, who last season at one point were leading the charts before a mid-term implosion that saw them have to settle for fourth, are hoping to again finish in the top spots in order to secure Champions League football for next season.

At the present, though, the London giants are in fifth place with 33 points, behind fourth-placed Southampton based on goal difference and should things not change between now and May, they will have to settle for playing in the Europa League during the 2015/2016 season.

Earlier today, they took on West Ham in the last league game of this year, which concluded as a 2-1 win in favour of the visitors thanks to goals from Santi Cazorla and Danny Welbeck.

However, the result could have been different. Earlier in the match, Cameroonian international Alex Song had opened the scoring inside the first five minutes with a long range effort, only to see it ruled out after the official judged his teammate Diafra Sakho to have been in an offside position.

And interestingly, despite his team ending up as the victors, the French tactician expressed his surprise that his former player's goal had not been counted.

"I didn't know why Alex Song's goal didn't stand, I thought it would," he mused following the match.

Alex Song expresses his disbelief after seeing his goal discounted against Arsenal

Not surprisingly, his counterpart on the opposing bench, Sam Allardyce was fuming after he felt his team had been robbed.

"We scored a perfectly good goal that was disallowed. It certainly should not have been disallowed on the basis of what Mike Riley and his staff tell us," he raged to reporters after their loss.

"The officials clearly got it horribly wrong and to say we are bitterly disappointed and frustrated is an understatement."