Borussia Dortmund head coach Jurgen Klopp has conceded that his side will be up against two "outstanding" players in Arsenal's Danny Welbeck and Alexis Sanchez tomorrow night.

The duo both joined the Gunners during the summer transfer window for what was reportedly a combined fee of £46m, and could line up in Arsenal's attack for their Champions League opener against Dortmund on Tuesday.

Speaking about the threat that they pose, Klopp told the London Evening Standard: "They have signed two outstanding players in Danny Welbeck and Alexis Sanchez, who will give them even more pace. I'm expecting the Gunners to try to utilise this on Tuesday."

Arsenal have met Dortmund six times in the Champions League and won on three of those occasions.