India, July 20 -- For nearly two years, a haunting question echoed through the halls of Indian badminton, growing louder with every tournament - is PV Sindhu done? At 31, a lingering foot injury and a subsequent rehab setback had left the two-time Olympic medallist and world champion at a career crossroads.

But on Sunday in Tokyo, those doubts were dispelled. Defeating home favourite and reigning world champion Akane Yamaguchi in straight games to capture the Japan Open title, Sindhu's triumph marked the culmination of a radical, data-driven transformation engineered by sports scientist Wayne Lombard.

When the South African was brought back into Sindhu's camp last October, he found an athlete stuck at a physical dead end. His first move...