Melisandre vs Saw: who would win?

Saw favored — Slight edge (~55%)

Melisandre · Game of Thrones · Base

Tier
9-B, up to 9-A
Attack Potency
Wall Level+, up to Small Building Level
Speed
Below Average Human, up to Average Human
Durability
Below Average Human Level, up to Human Level

Saw · Sakamoto Days · Base

Tier
9-B
Attack Potency
Wall Level+
Speed
Supersonic
Durability
Wall Level+

A heuristic estimate from normalized VS Battles Wiki stats: tier, attack potency, speed and durability.