The teenage Scot signed for the Gunners over the summer for a significant six-figure fee. Before making the move, Hammill made his senior debut for St Johnstone on the final day of the Scottish Premiership season against Dundee.
He told arsenal.com: "The interest from Arsenal started in February 2024. My mum took a phone call that lasted much longer than usual, and when she finally told me Arsenal wanted me on trial, I couldn't believe it. I joined up at Hale End and played my first game against St Albans, which we won 4-1 before being invited to travel to Germany with the under-18s.
"On the final day, Per Mertesacker and Jack Wilshere called me in for a chat. Per didn't give much away at first, so I wasn't sure what to expect, but when they offered me a scholarship, I was over the moon. The first thing I did was call my mum and dad, who were in tears of pride, and my friends couldn't believe it either. It was a surreal and unforgettable moment.
"Since arriving at Arsenal, I've loved every second. I've settled in brilliantly thanks to my team-mates, the coaching staff, and everyone who has supported me off the pitch. I'm proud to be one of the under-18s captains, as leadership is one of my strongest qualities, and I've also had the honour of captaining my country.
"I've already had the chance to train with the first-team, which was a fantastic experience. The biggest difference is the level of detail they work at, which is exactly what you'd expect from players competing at the very highest level. For me, it's all about learning, improving, and aiming to reach that standard myself."