A number of riders voiced concerns over the safety of the wet track which forced the start to be delayed for just over an hour.
And it seemed Bees’ rider King had little concern for the conditions as he flew from the start in his first ride of the night to win with ease ahead of Steve Worrall, Stefan Nielsen and Lewis Rose.
With other the favourites to win the meeting – Scott Nicholls and Tai Woffinden dropping points their opening rides – King knew he could take charge of the semi-final with a second straight win.
King came up trumps in heat eight putting on a ruthless display making it back-to-back wins ahead of fellow World Cup hopeful Craig Cook, who passed Charles Wright for second place.
Perhaps the biggest race of the meeting came in heat 11 with the Bees rider locking horns with 2013 World Champion Woffinden and seven-time British Champion Scott Nicholls.
However it was Adam Roynon who out-gated the trio taking the lead in superb style and held on until the last lap; when he lost control on the second bend letting Nicholls and Woffinden through while King fell while entering lap four.
That last place for King meant the Bees and Ipswich rider needed at least four points from his last two outings to secure his place at the British Final.
And in heat 14 King got a step closer to the final with an excellent ride after overtaking Carl Wilkinson round the boards to take the win.
In heat 17 the Great Britain squad member eventually rubber stamped his place in the final with a second place in his fifth and final ride.
With no less than five riders equal on 11 points after their qualifying races, it took much deliberation before Belle Vue captain Nicholls was declared the winner while King came second and Leigh Lanham in third.