It might well have been the most impactful January transfer that you didn't hear about, and going by his debut alone, Wu Lei signing for Espanyol might be one of the biggest signings of the whole season.

In the dying days of the winter transfer window, freshly eliminated from the AFC Asian Cup at the quarter-final stage, Wu Lei made an under-the-radar €2m move to La Liga hoping to become a trailblazer for Chinese football.

His record in the Chinese Super League is outstanding, with 27 goals in 29 games last season to cement him as the biggest star in the division. Trading Shanghai SIPG for Espanyol was always going to be a difficult decision, especially after 12 years of growth, success and then adulation in China's biggest city, but Chen Yansheng, Espanyol's billionaire owner, would not take no for an answer. Wu Lei was convinced to swap SIPG for Spain in a move designed to - and looking certain to - boost the popularity of Barcelona's second-biggest club in Asia.

Judging by the 40m fans that tuned in to Wu Lei's 12-minute cameo at the end of Espanyol's 2-2 draw at Villarreal, Yansheng might just have been onto something.

Chairman of the Rastar Group, Yansheng made his money principally through plastics and making toy and remote control cars. Now he is driving an ambitious project to make Espanyol a relevant club well beyond Spain's borders.

Wu Lei's unveiling had a reach of over 350m people in online streaming (Getty)

Chinese fans turned out to see Wu Lei's unveiling (Getty)

La Liga themselves have aggressively targeted China as one of their key growth markets and will continue to do so as the broadcasting arms race grows. Wu Lei's arrival in north-eastern Spain will only accelerate that, and while his brief substitute appearance managed to bring in 40m fans, according to data published by the club, the 350m reach of his presentation as an Espanyol player might be a more indicative number of how much interest there could be if Wu Lei starts playing regularly and even scoring.

The reigning golden boot winner and player of the year in the Chinese Super League appears to be under no illusions that the step up to La Liga is significant.