Voldemort seemed to be seeing right into Blaise’s soul and then after a moment he said "Very well..." and dug his wand into his arm. Blaise was not a quidditch player, he was not a fighter, he was spoilt by luxuries and simply watched what he ate to stay in shape. Taking a walk to class or to clear his head counted as exercise. If you looked at him you’d never believe he’d ever do anything to cause himself even a prickle of pain. And yet, as the Dark Mark was being seared into his skin, he grit his teeth as his eye teared up but he didn’t make a sound. Like Draco he also collapsed but his friend was by his side before he hit the ground.