A Gulfstream jet owned by Cristiano Ronaldo crash-landed in Barcelona on Monday evening -- but the soccer superstar was NOT on board at the time ... this according to multiple reports.
According to witnesses, the G200 -- which Ronaldo reportedly bought last year for $19 MILLION -- was landing at the El Prat airport when the landing gear broke.
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Ronaldo was in Germany at the time of the crash.
A source close to the superstar told The Mirror -- "The plane is normally rented by companies and it was in use by one of them.