in both stadiums. The lowest point was reached on 23 March 1997, when supporters of both clubs met on a field near Beverwijk, where Ajax-supporter Carlo Picornie was fatally injured, the incident is commonly referred to as the "Battle of Beverwijk". Rivalry with PSV PSV are also a rival of Ajax, but in terms of tension and rivalry, these matches are not as loaded as the duels with Feyenoord. The rivalry has existed for some time with PSV and stems from various causes, such as the different interpretations of whether current national and international successes of both clubs correlates and the supposed opposition between the Randstad and the province. The matches between these two teams is commonly referred to as "De Topper" ("The Topper"), and involves the two most trophy-laden sides in Dutch football and is essentially a clash of two competing schools of thought in Dutch football. Historically, PSV compete with a workmanlike ethic, preferring a more robust 4–3–1–2 or 4–2–3–1, typically shunning the frivolous 4–3–3 approach favoured in Amsterdam. While Rinus Michels and Johan Cruyff helped to innovate Total Football in the sixties and seventies, a different philosophy was honed in Eindhoven by Kees Rijvers and Guus Hiddink in the late 1970s and '80s. This in turn has created one of the more philosophical rivalries in football, an ideological battleground, which is gradually becoming as heated and intense as the matches Ajax and Feyenoord partake in. Rivalries with other clubs Aside from Feyenoord and PSV, Ajax have several other rivalries, although in most cases the sentiment is mostly felt by the opposition and is more directed towards Ajax, with one of them being Utrecht. Although the rivalry is more felt on the Utrecht side then with Ajax, matchups between the two sides are often quite intense. Both teams have fanatic supporters, and clashes off the pitch are more often the rule than the exception. The same goes for ADO Den Haag, with both supporter groups often getting in conflicts, when ADO-Hooligans set fire to the supporters home of Ajax, and Ajax hooligans subsequently broke into the Supporters home of ADO tensions between the two clubs rose. In 2006, supporters from both clubs were banned from attending away matches for five years due to frequent violent outbreaks and clashes. Further teams who share a rivalry with Ajax include Twente, Vitesse Arnhem, Groningen and AZ, although the latter is often