Fighters aren’t usually the blushing type. But Xu Xiaodong can’t hide his embarrassment when asked about his latest battle scar, a three-inch crimson railroad track that snakes over his right eyebrow. It was caused, he says, by an overzealous opponent’s knee at a recent training session, during which Xu grappled with four younger mixed-martial-arts (MMA) fighters in quick succession. “I was tired by the end and bam!” Xu tells TIME in his Beijing gym. “Twenty-six stitches!”
It’s by far the most obvious of the 40-year-old’s war wounds, eclipsing even cauliflower ears and a catalog of creaking bones. But it’s nowhere near the deepest. Xu has spent a lifetime fighting, first at school and later channeling a red-hot adolescent temper into competitive MMA. But the fiercest blows he suffered were far from the ring, when he took on practitioners of traditional Chinese martial arts, known officially as wushu but more colloquially as simply kung fu.