Arsenal’s star forward Alexis Sanchez may have ankle ligament damage after under-fire boss Arsene Wenger admitted the Chilean overruled him in staying on the pitch during their dreadful 3-1 defeat at West Brom today.

The 28-year-old’s right ankle was described by the long-serving Frenchman as being in an ‘absolutely terrible state’ after a first half challenge by former Wigan player James McClean.

However, the Topocilla-born frontman – who hit his 18th goal in 25 Premier League starts at The Hawthorns as the Gunners were outclassed by Tony Pulis’ vibrant team – played on until deep in the second half before he was substituted for Alex Iwobi with 12 minutes remaining.

Arsenal will monitor any potential ligament injury but under-pressure Wenger conceded after the match that Sanchez “should not have played in the second half but he insisted that he wanted to – in the end we had to take him off.”

The North Lonodoner’s next match is after the international break on Sunday, April 2 against FA Cup semi-final opponents Manchester City but Sanchez is in Chile’s squad for World Cup qualifiers against Argentina and Venezuela with the game against Edgardo Bauza’s Albicesleste in Buenos Aires on Thursday.

Asked if Sanchez would be fit to play for his country, Wenger said: “If it’s only a kick, he will play. If the ligament is damaged, he will not play.”

It was a dispiriting day for Wenger in terms of injuries after experienced goalkeeper Petr Cech had to be replaced by David Ospina on 37 minutes to a calf injury at as Arsenal fell to a third 3-1 defeat on the road in a row, following losses at Chelsea, Anfield and now The Hawthorns – suffering their fourth defeat in five league games.

The result now leaves them five points behind Jurgen Klopp’s Liverpool with a game in hand.

Wenger caused more speculation by saying after the game that he had already decided on his future, saying: “I know what I will do – you will know soon, very soon.

You will see. We are in a unique bad patch we have never had in 20 years where we lose game after game. That is more important.

“We have a big fight to finish in the top four – it will be very difficult now.

“If we don’t do it we have to live with the consequences.”