Pre Nail Piccolo & Vegeta (vs 1st form Freeza) vs 1st form Freeza

[Natasha Romanoff]

Who wins?

Obviously talking about the Piccolo that arrived to Namek. Let's assume that Piccolo is reckless and reject Nail's offer going straight to the battlefield. Vegeta and him decide to fight Freeza, while lefting Gohan and Krillin as spectators.

Freeza is not allowed to transform.

 

[SSJ2]

Freeza gets overwhelmed here. Vegeta was already close enough to evenly clash with him hand to hand. Piccolo might be a little too far behind to do serious damage but he can at least act as a punching bag to distract Freeza.