Arsenal intend to take their time over appointing Edu’s successor as sporting director, with his deputy, Jason Ayto, set to step until the recruitment process has been completed.

Mikel Arteta admitted before Wednesday’s 1-0 defeat at Inter that the Brazilian’s departure had taken Arsenal by surprise and “everything happened very quickly”. It is understood that Edu – who is expected to join the multi-club network of Nottingham Forest’s owner, Evangelos Marinakis, on a reported £5m a year – is beginning a six-month notice period with reduced responsibilities as Arsenal look for a replacement.

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Arteta is expected to play a key role in that decision along with the rest of Arsenal’s leadership group, which also includes the executive vice-chair, Tim Lewis, and Richard Garlick, who was promoted from director of football operations to managing director in the summer. It is believed they have yet to target an individual but want someone who can work closely with the Arsenal manager and attempt to build on the club’s progress in recent seasons.

Ayto, who was promoted to assistant sporting director last April, is expected to step into the breach as they prepare for the January transfer window. The 38-year-old is highly regarded at Arsenal, where he started as a video scout in 2014 and worked his way up via his role as recruitment coordinator. He could come under consideration for the permanent role, although Arsenal are thought to be targeting a more experienced sporting director and could be prepared to wait as long as six months for the right person.

Arsenal’s hierarchy are set for a meeting with the owner, Stan Kroenke, and his son Josh, the co-chair, in the United States during next week’s international break, when they will discuss next summer’s transfer window. Although the team trail the Premier League leaders, Liverpool, by seven points after a testing start to the season, it is understood they are unlikely to bring in expensive signings in January unless important players sustain injuries.

Kai Havertz and Mikel Merino are expected to be available for Sunday’s game at Chelsea after being substituted against Inter and Declan Rice – who did not travel to Italy owing to a broken toe – is also expected to feature after being named in the England squad on Thursday. The captain, Martin Ødegaard, came on as a late replacement after missing Arsenal’s previous 12 matches with an ankle injury.

Arsenal racked up 20 attempts and had almost 63% possession at San Siro but could not find a way through Inter’s defence. “It was very tough, very frustrating for us,” said the defender Jurriën Timber. “I think we played a good game. We dominated a lot but we didn’t score.”

He is confident regarding the visit to Stamford Bridge: “It will be tough again but I believe in our squad – we have a lot of quality and 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.”