Arsenal have begun investigation into Nicolas Pepe’s surprising £72m transfer as part of efforts to improve the club.

25-years-old Pepe signed the deal from Lille last year after attracting interests from top Europeans clubs having impressed in the Ligue 1.

The Ivory Coast international finished his debut season in England with eight goals and 10 assists across all competitions; a satisfactory return despite some inconsistent form.

Although, Arsenal have since denied the investigation, ESPN have disclosed that sources in three club have confirmed that Arsenal is investigating whether Pepe was overpaid.

Sources also said there is no sign of regret but many are still surprised at the £72m as Arsenal is notoriously known to be very prudent in their finances.

The Gunners paid £20m up front but have committed a further £52m over the next five years, the first instalment of which is due this summer. As a result, scouting reports and negotiating process have been subjected under Review which could lead to sanctions.

Technical director Edu held up Pepe’s shirt with the winger at his unveiling, though he was not a key part of the transfer deal as he joined Arsenal three weeks after Pepe joined the club.

Former Gunners head coach Unai Emery had reportedly preferred Wilfred Zaha but Crystal Palace wanted the majority of a similar fee up front and Arsenal went for Pepe instead.

However, Lille president Gerard Lopez has said that Arsenal did not overpay for Pepe.

He also denied reports that Pepe’s transfer was the reason why Arsenal’s head of football Raul Sanllehi left the club.

Lopez told Sky Sports News: “I think it is made up stuff.

“I know for a fact he has an excellent relationship with the club and they left on excellent terms.

“There are always going to be stories that try to be interesting, Arsenal are going through a restructuring which is part of what happens. He is a great guy, it is a great club and as far as I can see they both [Arsenal and Sanllehi] respect each other immensely.

“They have a player [Pepe] where people forget his age, and the fact he took one season to click within our system and then became the player which we all know.

“He has had a good second half of the season at Arsenal and he is one of the rare players who can make something happen from nothing.

“The more comfortable he gets at the club, the more he will make things happen so I think the best is yet to come.”

FrujuSports had reported that Raul Sanllehi left Arsenal and was replaced by Vinai Venkatesham.