This is a good step up for Fisher who is only 2-0 with his first two fights being against journeymen. Danny Whitaker is a domestic heavyweight who’s had mixed results leaving him with a record of 4-3.
Johnny Fisher showed decent power and athleticism in his first two fights and has had good sparring in recent months. Danny Whitaker isn’t as athletic as Fisher and has shown no power as a heavyweight which is a major disadvantage for him.

I think Fisher will likely stop Whitaker in the third or fourth round due to having more power and having more urgency in the ring. Fisher is really better all round but Whitaker should hopefully provide a bit more of a test than his first two opponents.