Arsene Wenger says Barcelona will need to do more than just change their manager if they wish to bounce back as their "exceptional generation is coming to an end".
Despite a period of dominance the Spanish giants have now gone five years without winning the Champions League and surrendered the La Liga title this season.
It was their exit from Europe which laid bare their current plight after an 8-2 mauling at the hands of Bayern Munich in the quarter-finals.
Former manager Quique Setien was sacked in the aftermath as Barcelona's board wielded the axe before appointing Koeman in his place.
Read more on mirror.co.uk