Mikel Arteta says new signing Riccardo Calafiori told him weeks ago: 'My bags are packed, I just want to join Arsenal.'
The Italian is now hoping to feature against Liverpool this Wednesday.
The 22-year-old Bologna defender signed a five-year contract with Arsenal, worth around £42million, and joined the squad in Philadelphia on Monday.
Arteta said: 'I spoke to him one or two times and I wasn't sure if we could do it or not.
'He was adamant, "Let me know when you're ready, my bags are packed and I just want to join Arsenal". Those were his words.
Riccardo Calafiori pictured (right) signing his Arsenal contract next to manager Mikel Arteta
Calafiori will wear the No 33 shirt following his £42million transfer from Bologna in Italy
'When you have someone with that willingness and that passion to join and make us better and that determination it's really powerful. As a club we should be really proud of that.'
Arsenal play Liverpool on Wednesday at the Lincoln Financial Field where Calafiori could feature.
'I don't know, he had a long flight yesterday and the medical,' said Arteta on Monday.
'The last 48 hours have been busy for him. He hasn't really done anything with the team. Let's see how he is.
'If he's available great, he might play a few minutes. But if he's not ready, we're not going to push him.'
On what the Italian brings to his side, Arteta added: 'He is a player that we have monitored for about a year. We were really short in the backline last season in terms of numbers. We demanded so much from them.
According to Arteta, Calafiori was 'adamant' that he was going to move to Arsenal this summer
Calafiori has joined up with the Arsenal squad on their pre-season tour of the United States
'Willy [Saliba] for example played every minute of the Premier League and we believe that we have to make them much more protected.
'We identified him [Calafiori] as a top player, a talent who has the skills and qualities that are going to make us better. He is still a player with a huge capacity to develop.'