A select few players who have played for both clubs.
Niall Quinn (Arsenal 1983- 1990, SAFC 1996-2002)
Uniquely player, manager and chairman and hugely influential figure since firstly impressing as a first-class target man with supreme heading ability and deft ball skills. At its peak his lethal partnership with Kevin Phillips yielded 128 League goals in three seasons and later his off the field efforts were integral to the stabilizing of the club following relegation in 2006.
Quinn joined Arsenal from Irish junior football in November 1983, but he made his debut two years later, scoring against Liverpool at Highbury. The highlight of his spell with the Gunners was a 1987 League Cup winner’s medal. He moved onto Manchester City in 1990 for £800,000.
Steve Bould (Arsenal 1988-1999, SAFC 1999-2000)
Moved to Arsenal for a fee of £390,000 in 1988 from Stoke City, and became part of Arsenal's "famous back four" defensive line-up, with Tony Adams, Nigel Winterburn and Lee Dixon. Bould won the First Division title twice in 1988–89 and 1990–91. He was voted player of the year by the club's fans for the 1991–92 season. He also won the Cup Winners Cup in 1993-94 as well as the double in 1997-98.
Bould joined the Black Cats following the promotion in 1999 and was made club captain by then manager Peter Reid. He helped the Black Cats to a seventh place finish. However injuries limited his appearances and he retired in 2000.
Stefan Schwarz (Arsenal 1994-1995, SAFC 1999-2003)
The well travelled Swedish international midfielder only played for one season at Arsenal but did enough to make a lasting impression with everyone connected at the club. Signed from Benfica in the summer of 1994, he was a pivotal figure in the Club's run to the 1995 European Cup Winners' Cup Final, where Nyaim’s freakish goal prevented the Gunners from lifting the trophy. Schwarz moved on in the summer of 1995 as new manager Bruce Rioch signed David Platt.
Schwarz added international experience to the Black Cats midfield when signing aged 30 for a then club record fee of £4 million following promotion in 1999.Allied crisp passing to decisive tackling and the occasional superb goal but injuries limited his appearances.