What does it take to promote a sport from scratch? For husband-and-wife pioneers Zhang Lei and Wang Nuo, the answer is being carved out on pickleball courts – from schoolyards to the China Open. Now, former Belgian Prime Minister Yves Leterme joins them to see  firsthand how a grassroots passion project evolves into a national movement, offering a unique lens on the country's booming sports culture. Click to get the big picture!