The question now for the French club is how to rebuild without its record scorer: keep pouring money on big-name signings or find another way to compete with Europe's best?

When he leaves at the end of the season, Mbappé will join Zlatan Ibrahimovic, Edinson Cavani, Thiago Silva, Ángel Di María, Neymar and Lionel Messi in having failed to deliver the elusive Champions League trophy — despite the club's Qatari investors spending more than 2 billion euros ($2.15 billion) in transfer fees since taking over in 2011.

Now that era of Galácticos could end when Mbappé plays his last game for PSG in the French Cup final against Lyon on May 25.

Replacing him will be difficult, no matter how much money the club spends. The France forward has scored 255 goals for PSG, and his prolific output helped deliver six league titles in seven years — but also often masked glaring deficiencies that were exposed at the highest level in the Champions League.

This season, PSG won just five of its 12 games in Europe, losing five and drawing two. So how can it possibly get more competitive without its best player?

Club president Nasser Al-Khelaifi has many key decisions to make as PSG kicks off its new era.

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