Petrauskas picked up from where he left off in his last bout and waded forward with a high guard before trying to rough his opponent up on the inside.
The South Korean soaked up all his pressure and was moving side to side nicely and landing a few decent shots.
Han led by two points as they entered the final three minutes, but came under some intense pressure from the Lithuanian.
Pretrauskas's tactics were still the same, but he was swinging wildly and not landing effectively.
Han kept his composure and continued to box well off the back foot to clinch a 18-13 victory.