In the vs battle wiki saitama is a 9-B tier | 9-A, up to at least 8-B | At least High 6-A, likely much higher.
While Goku is a 3-A tier and higher in his other forms | 3-A | 3-A | Low 2-C | 3-A, Low 2-C as Super Saiyan Blue | Low 2-C
So therefore Goku take this cake and stop the biases