It is a big blow for the Premier League title contenders, with Havertz missing 12 league matches last term between February and May last season due to a hamstring problem. Ornstein claims the Gunners recruitment chiefs are exploring the transfer market to potentially reinforce their attack and cover the absence of Havertz.

Arsenal had an open training session at the Emirates on Wednesday before their first home fixture of the Premier League season when they host Leeds United on Saturday. Ben White and Kai Havertz were glaring omissions. White came off in the 71st minute in the win at Manchester United on Sunday and Havertz started the game on the bench.

Arsenal are moving for Crystal Palace's Eberechi Eze after learning Kai Havertz has suffered a potentially serious knee injury, sources told ESPN.

Havertz, who earns £250,000-a-week at the Emirates Stadium, was Arsenal's main man in attack last season, but he's since been joined by Viktor Gyokeres as another option for the centre-forward position. As a result, Havertz was on the bench against Manchester United at the weekend, with Gyokeres leading the line for the Gunners.