Asajj Ventress vs Count Dooku (AotC)

Ventress is at her peak fighting AotC Dooku.

Ventress gets wrecked

Dooku kept secrets from Ventress so that should she ever grow powerful enough she was still not a threat to him.

In a sabers only scenario I could see her contending somewhat, albeit losing. But since Dooku can just lift a finger and force her to drop to her knees via a technique she can't defend against, Dooku solidly dismantles her or just oneshots 

Ventress can hold her own in sabers for a time but gets utterly destroyed in the Force due to the knowledge and power disparity.