Qian Yu had used all of his secret weapons during the battle. He had even used the rare mermaid king bloodline in the Diving Songstress' body.
This was not because he saw this battle as life or death but because he would be able to use his accomplishments during this battle to obtain even better status and more resources when he returned to the Freedom Federation.
Qian Yu actually had a safety net set up.
No matter what happened, even if he really ended up fully held down by his opponent, the Goddess of Mercy would not sit by and watch him die.
The Goddess of Mercy had come to the Radiance Federation because she had been worried for his safety.
Qian Yu was intelligent and could sense how the Goddess of Mercy felt about him. He knew that she did not dote on him like how Na Na doted on Lu Ou. Rather, she had an ulterior motive for treating him so well.