By Tony Hughes

Alexis Sanchez is facing a lengthy spell on the sidelines after suffering a suspected calf injury, according to a report.

CNN Chile claim the forward reported for international duty before leaving training with his national team early on Tuesday afternoon to undergo medical tests for a suspected torn calf muscle.

It is said that there has not yet been a definitive verdict but Arsenal will be braced for what could now be a devastating blow to one of their star players.

Sanchez could be facing months on the sidelines if tests confirm that he has torn a muscle in his calf.

Sanchez has been in sensational form for Arsenal this season after being handed a new role as the spearhead of the attack.

He has responded with eight goals and seven assists from 15 matches in all competitions and has been a key player in the Gunners’ 16-game unbeaten run.

Arsenal have entered the international fourth in the league with 24 points from their opening 11 matches, just two points behind leaders Liverpool.

Sanchez, 27, has spoken of his confidence that Arsene Wenger’s side can mount a genuine title challenge in what is his third season at Emirates Stadium.

“We’ve got some new players and a fantastic squad. Regardless of who’s playing, we all need to be 100 per cent focused on our work with the team and the club,” the Chile international said.

“Everything comes down to what happens from now on. All games are different and anything can happen in football. An important player might get injured – someone might leave, someone else might stay. It’s tough to keep it going, but if we stick together and keep putting the running in, I think this team can win it all.”

Arsenal’s next two matches are against Manchester United and Paris Saint-Germain.

In other Arsenal team news, the club are moving closer to securing a new long-term deal for one of their most-prized assets.