De boer only lasted 4 Premier league games. Guillet started managing in the Prem and wasn't considered a great success. Riikard started internationally and only had a short spell in Holland.
As for Cocu...
"Coach Philip Cocu has been relieved of his duties, Istanbul giants Fenerbahçe announced in a statement late Sunday. Under the Dutchman's supervision, Fenerbahçe failed to qualify for the Champions League and is now placed 15th in the Super League, just above the relegation zone by a point.
The 47-year-old Cocu, who only took over in June, has seen Fenerbahce, one of the country's traditional footballing powerhouses, slump to 15th in the Turkish Super League, just one spot above the relegation zone. The team has long been considering parting ways with the coach, especially after the recent Rize thrashing."