Benfica president Rui Costa is baffled by reports of an Arsenal offer for Alejandro Grimaldo.

With Nuno Tavares a target for Olympique Marseille, Arsenal are moving for Grimaldo as a replacement at left-back.

However, Rui Costa insists there's been no formal offer made.

"I'm going to talk to him now, see if he's okay," Costa told a reporter when asked about Grimaldo's situation. "Grimaldo is like all the other players, he is working and in time we will..."

At that point, Costa was interrupted by another reporter to see if Arsenal have made a bid.

"You [the press] have been saying that," came the reply. "None of this came to me. I don't know where that came from."

Grimaldo has less than a year to run on his Benfica deal.