Since signing from Reading, the 21-year-old has proven to be an exciting young talent at the Eagles.
Olise capped off his first season with four goals and eight assists before concluding the previous campaign with 13 contributions.
Given Palace's successful second half of the campaign under Roy Hodgson, they would have been looking to push on from the get-go next term.
However, their plans for the new season appear to have been dealt as a blow as Olise look set to miss their opening games.
Whilst playing for the France in the Euro U21s Championship against Norway on Sunday, the Daily Mail report that he suffered a serious grade 3 hamstring tear.
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A collision with Norway and Leeds goalkeeper Kristoffer Klaesson saw him pick up the injury that could sideline him for some time.
Olise had scored the only goal in France's 1-0 win moments beforehand as they sit top of Group D.
It remains to be seen how long he will be out of action for, but it looks as though a lengthy spell on the sidelines is required for recovery.
He is now ruled out for the rest of the Euro U21 Championship and will be focusing on a return to the pitch as soon as possible.
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Palace will likely have to make do without him when the new Premier League season kicks-off in August.
A trip to newly-promoted Sheffield United awaits them on the opening weekend of the campaign.
However, their return to Selhurst Park will see them come up against Arsenal the following week.
Brentford, Wolves and Villa make up the final opponents for Palace in the first five fixtures as they look to build upon their 12th-placed finish.