#4 Axel Witsel (Tianjin Quanjian)
It seems like Witsel has been on the radar of big European clubs for years now, but the rangy midfielder is still only 29.
Before moving to Tianjin in 2017, the Belgian had been playing for Zenit St Petersburg in Russian football for 4 seasons, winning the league title in 2015. A tall, elegant central midfielder with good passing ability, Witsel seemed destined to make the move to one of top 5 European leagues.
Chelsea were interested in acquiring his services a season ago but he moved to China. It's not hard to imagine Witsel offering a nice balance to the all-action defensive style of N'Golo Kante had he moved to England instead.
Strikers often enjoy moving to less difficult leagues because it usually means they have more chances than they would in Europe due to weaker defences, meaning more goals as a result, but for a midfielder, sometimes the action isn't as intense as they're used to and relish.
Andrea Pirlo looked lost during a lot of MLS games during his time at New York City FC, for instance.
In a World Cup year too, it's imperative that Witsel impresses Belgium manager Roberto Martinez to make the squad. He's been a starter for his country for almost a decade now, but one can't help to think that playing in Europe would have helped his chances more.
Witsel will have to really stand out from China if he's to continue as a first team member for his national side.