Чемпионат Чехии по футболу
During the 2010–11 season, Mendy played all 30 league games for FK Mladá Boleslav scoring six goals as he helped them finish in fifth place in the Gambrinus Liga and also win the Czech Cup for the first time in Boleslav's history after beating SK Sigma Olomouc on penalties, Mendy scored one of the penalties for Mladá Boleslav in the final. The Cup win also saw Boleslav qualify for the UEFA Europa League for the following season. After his contract with FK Mladá Boleslav expired in June 2011, Mendy sought pastures new and became a free agent. He has found the back of the net 24 times in 207 appearances in the Gambrinus Liga.