Arsenal have begun their search for a new sporting director with Jason Ayto stepping up to fill the vacancy on an interim basis following Edu’s sudden resignation.

The Gunners’ turbulent week suffered another setback on Wednesday night after a contentious 1-0 defeat at Inter Milan in the Champions League.

Manager Mikel Arteta was left furious with two penalty decisions – one awarded against his side in first-half stoppage time, duly converted by Hakan Calhanoglu – and the other when Inter goalkeeper Yann Sommer’s collision with Mikel Merino went unpunished.

A wounded Arsenal will now travel to Chelsea on Sunday as they bid to get their stuttering Premier League campaign back on track before moving to tackle the void left by Edu.

The former midfielder, integral to Arsenal’s upturn in recent seasons, left his post on Monday ahead of a lucrative link-up with Nottingham Forest owner Evangelos Marinakis.

The PA news agency has been told that Ayto, who acted as Edu’s number two, will take temporary charge of the role as the club draw up candidates for a permanent successor.

Arteta said on the eve of Arsenal’s defeat in the San Siro that he had a “special chemistry” with Edu – with club sources moving to deny speculation of a falling out between the two.

Arteta, managing director Richard Garlick, and executive vice-chair Tim Lewis will all be involved in the selection process, along with the club’s ownership.

A delegation is expected to fly to the United States to meet with Kroenke Sports & Entertainment (KSE) – headed by chairman Stan Kroenke and his son and co-chairman Josh Kroenke – during this month’s international break to discuss the next steps.

Assistant sporting director Ayto will be considered a safe pair of hands. He has been at the club for a decade, first as a scout, before working his way up the ladder to become Edu’s right-hand man last year.

Ayto’s elevation comes at a problematic time for the club. Following a strong start to the season, they have taken just one point from their last three matches in the Premier League to slip seven points adrift of Liverpool. Their defeat in the San Siro – the club’s second in four days – leaves them 12th at the midway stage of the 36-team division.

Reflecting on Arsenal’s latest setback, defender Jurrien Timber said: “It’s very tough and very frustrating for us. We played a good game, we dominated a lot but we didn’t score. In the Champions League, you have to score if you want to win.

“It’s a tough away game and small moments can decide a game.

“On Sunday, it will be tough again, but I believe in our squad. We have a lot of quality, we just need a little bit of luck in scoring more goals. I have a lot of trust in our team and we’ll be fine for sure.”