The 23-year-old excelled at FC Twente, coming out of The Tukkers' academy, before moving to Benfica where he made 55 appearances, registering just three goals. Since then the £10 million man moved to Hamburger SV on loan but failed to make an impact in the Bundesliga, returning after only eight first-team outings.
The next step in the winger's career, then, is to Berkshire and a loan deal until the end of the season confirmed on this transfer deadline day by the club.
Steve Clarke told the official website:
"He is an attacker with power and pace, the ability to beat a man and deliver quality balls into the box and also an eye for a goal himself. With these qualities, added to the players we already have in the club, Ola should help ensure that we are a more potent attacking team this season."
With one cap for the Dutch national side, John is the latest Oranje star with once-unimaginable potential to find his way to the Madejski Stadium, and he comes after the less-than-successful spells of Royston Drenthe and Peter Van Der Kwaak. He will compete with the likes Paolo Hurtado, Garath McCleary and Tarique Fosu for a spot on Reading's flanks.
Is this a good signing? Have we enough wingers? Comment below.