Cristiano Ronaldo Has Fun on Flyboard in Mediterranean Sea Near Ibiza with Girlfriend

Cristiano Ronaldo can move like nobody else on the pitch ... but still has some work to do before he looks as graceful on water.

The famous soccer star showed off his flyboarding skills in the sea near Ibiza ... but had to take a dive when the jet pack didn't go the way he expected. All good, though ... he could just regroup on his mega yacht.

Ronaldo's in Spain with his gf Georgina Rodriguez, who had some fun on a jet ski herself.