While he may be the main story of the day, we take a look at three other players who have played for both, including a goalkeeper signed by George Graham, a defender who featured in the 'Invincibles' side and a former Portsmouth midfielder.
Garry joined Arsenal in 1999 and progressed all their way through their academy, with the highlight being a 2001 FA Youth Cup victory.
He progressed to the first-team fold and made his debut in a 6-1 victory over Southampton, the first match of Arsenal's 49-game unbeaten run, which saw Jermaine Pennant and Robert Pires both net hat-tricks.
But after a series of injuries which kept him on the sidelines for four years, he left the Gunners in 2006.
2007 saw him sign for the Cherries but injury would rear its head again, forcing Garry to retire in 2011. He's now the Arsenal Academy's under-13s coach.
Signed from Wolves in 1991, Bartram was an ever present in his first season with the Cherries.
He spent three years at Dean Court and became extremely sought after, before Arsenal bid £250,000 to join the London club.
Bartram became David Seaman's understudy at Highbury and was restricted to 11 appearances, before joining Gillingham.
Hughes began his career as a youth player in Italy with Serie A outfit Atalanta.
But he moved back to the UK and was picked up by Arsenal's academy. Hughes spent some time there before leaving to join the Cherries in 1998.
He enjoyed a fruitful spell on the south coast with Portsmouth and the Cherries again in 2012, before retiring after a successful career in 2014.