Who would win? DEATHMATCH: Saurophaganax vs Stegosaurus

Saurophaganax maximus: 11.75m/38.5ft long, 3.7m/12ft tall.

Stegosaurus stenops: 9m/29.5ft long, 5m/16.4ft tall

Rules: Stego is alone. Sauro is alone. No other dinosaurs around. No use of environment (Trees falling on enemies, hiding behind something, etc.).