Left back Jan Everse played for Feyenoord between 1972 and 1977, making 46 appearances before joining Ajax, where he played 69 games until 1980.
Denmark striker Jan Sorensen arrived at Feyenoord for one season in 1985, scoring nine goals in 25 games before joining Excelsior for another season in 1986. He then joined Ajax for a brief period in 1987, making just five appearances for them.
Dutch goalkeeper Kenneth Vermeer graduated from Ajax's academy before making 103 senior appearances for the club between 2005 and 2014. He joined Feyenoord and went on to make 101 appearances for them.
Dean Gorre was signed by Feyenoord in 1992. The midfielder stayed at the club for three years, making 42 appearances before joining Groningen. In 1997, Ajax signed him and he made 36 appearances for them in two years, scoring four goals.
Dutch attacking midfielder Richard Knopper was an academy graduate at Feyenoord before Ajax signed him up for their academy. He signed his senior contract with Ajax in 1997 and stayed there for six years, making 67 appearances and scoring 19 goals.
Goalkeeper Henk Timmer made a combined 415 appearances for Zwolle and AZ between 1989 and 2006. Between these years, he spent the 2001-02 season with Feyenoord and the 2002-03 season with Ajax on loan. Feyenoord signed him permanently in 2006 and he made 94 appearances for them.
Brazilian winger Leonardo arrived at Feyenoord's academy at a young age and went on to break into their senior team in 2005. In his five years there, he made 53 appearances. He joined NCA Breda in 2006 before joining Ajax in 2007, where he spent two years, playing 39 games. Leonardo spent his professional career's final year with PSV, thus completing the trinity of Dutch football by playing in all three top teams in the land.
Evander Sno graduated from Ajax's academy and was immediately signed by Feyenoord in 2005. However, he failed to make a single appearance for them before leaving in 2006 for Celtic. He returned to Ajax in 2008 and played 19 games for them.
Goalkeeper Ronald Graafland spent two years at Feyenoord at the start of his career but failed to make a single appearance for them. Excelsior signed him in 2000 followed by Vitesse in 2008. Ajax came calling in 2010, but he couldn't make the cut there before returning to Feyenoord in 2011.
Netherlands winger Anwar El-Ghazi was with the Feyenoord academy between 2006 and 2008 before joining other clubs and eventually arriving at Ajax in 2013. The former Aston Villa man joined PSV in 2022.
Kostas Lamprou played as a goalkeeper for Feyenoord, making 14 appearances between 2009 and 2015. He then joined Willem II before joining Ajax in 2017. In his two years at Ajax, he made just three appearances.
Morocco winger Oussama Idrissi arrived at Ajax as part of a loan from Sevilla in 2021. He made seven appearances for them before joining Cadiz on loan in 2022. After playing 12 games for the Spanish team, he joined Feyenoord for the 2022-23 season.
Central midfielder Rene Notten joined Ajax in 1974 and made 91 appearances for them before joining Feyenoord in 1978. He scored 22 goals in 127 games for Feyenoord.
Johnny Rep was one of the best players at Ajax in the early 1970s. The winger played for them between 1971 and 1975, scoring 41 goals in 97 games, winning back-to-back European Cups in 1971-72 and 1972-73, among other trophies. He then played for clubs like Valencia, Bastia, Saint-Etienne and Zwolle before joining Feyenoord in 1984. Rep made 43 appearances for them.
Three-time Eredivisie winner with Ajax, Keje Molenaar signed for them from Volendam in 1980 and went on to make 89 appearances. The defender loved scoring goals and found the back of the net 22 in his time at Ajax. He returned to Volendam for one season in 1984 before joining Feyenoord. Between 1985 and 1988, he made 100 appearances for Feyenoord, scoring 11 goals.
Born to a Chinese father and Dutch mother, Tscheu La Ling signed for Ajax in 1975 and went on to become one of their greatest wingers. He made 172 appearances for Ajax, scoring 54 goals. He left the club in 1982 and after a couple of stints abroad, La Ling returned back to the Netherlands in 1985, this time with Feyenoord. He spent a season there, making 18 appearances.
Martin van Geel joined Ajax from Willem II in 1979. He stayed there for two seasons, making 22 appearances and winning one Eredivisie title in his first season. He moved to Roda JC in 1981 and spent the majority of his career there before moving to Feyenoord in 1988. Van Geel spent two seasons at Feyenoord, scoring 24 goals in 50 games.
Ajax academy graduate Harvey Esajas never got a chance to play for their senior team, but Feyenoord granted him his senior debut in 1993. The defender played there for three years, making eight appearances.
Ajax signed John van Loen from Anderlecht in 1991. He spent two seasons at the club, making 37 appearances. Feyenoord made a move for the striker in 1993, where he spent another two seasons, scoring 17 goals in 54 games.
Dutch forward Peter van Vossen joined Ajax from Anderlecht in 1993. In his two years there, Van Vossen made 41 appearances, scoring six goals before joining Istanbulspor and later, Rangers. In 1998, Feyenoord came calling. He made 73 appearances in three years for the club, scoring 10 goals.
Diego Biseswar joined Ajax's academy in 1994 and stayed there until 1999. He later joined and graduated from Feyenoord's academy in 2005 and went on to make 95 appearances for their senior team, scoring 11 goals.
Feyenoord signed Evander Sno from Ajax's academy, but he failed to make a single appearance for them. In 2006, he signed for Celtic. Ajax brought him back in 2008. He left the club after a three-year stint.
Angelos Charisteas played for Ajax and Feyenoord in back-to-back seasons. The striker signed for Ajax in 2005 and scored 12 goals in 31 appearances. He left the club to join Feyenoord in 2006 and scored nine goals in 28 appearances before joining Nurnberg.
AZ Alkmaar signed Tim de Cler from Ajax in 2002. The left-back made 75 appearances for Ajax. At AZ, he established himself, playing 157 games before joining Feyenoord in 2007, where he played 87 games.
Ronald Graafland is quite a forgotten name in Feyenoord and Ajax's history. The reason is the goalkeeper made no appearances for Ajax and just one appearance for Feyenoord.
Feyenoord signed John Goosens in 2012. He made 30 appearances for them in two years, before moving to the Indian Super League club FC Pune City. The midfielder then moved to Voluntari in Romania in 2015 and Chicago Fire in the MLS in 2016.
Bilal Basacikoglu joined Ajax's youth academy but joined Heerenveen at senior level in 2013. A season later, Feyenoord signed the winger. He made 78 appearances for them.
After spending his youth academy days at Ajax, Warner Hahn joined FC Dordrecht in 2012. The goalkeeper was signed by Feyenoord in 2014, but failed to make a single appearance for them.
Netherlands midfielder Marko Vejinovic graduated from Ajax's youth academy, but did not make it to their first team. He enjoyed senior stints at AZ, Heracles Almelo and Vitesse before Feyenoord signed him in 2015. Vejinovic stayed there for two years before returning to AZ.
After making just two senior appearances for Ajax, Jan-Arie van der Heijden joined Vitesse in 2011. The defender established himself at the Arnhem-based club, eventually signing for Feyenoord in 2015. In his five years there, he made 97 appearances.
Eljero Elia featured for Ajax's youth academy between 2000 and 2002. But at senior level, the winger played for Feyenoord between 2015 and 2017, scoring 17 goals in 55 games.
After impressing with Ajax's reserve team Jong Ajax, Danilo was promoted to the first team in 2020. However, the striker was limited to just 14 appearances in his two years at the club which included a season-long loan to Twente in 2020-21, where he scored 17 goals in 33 games. Feyenoord signed the Brazilian in 2022.