King took silver in the men’s 60m hurdles at the British Indoor Championships behind current world number one Andy Pozzi.
The former Devonport High School for Boys pupil had run the British Athletics’ tough 7.65 second qualifying time last week in France.
It meant he went to South Yorkshire knowing he just had to finish in the top two to be on the plane to Serbia for the Europeans, which take place March 3-5.
King, who represented GB at last summer’s outdoor European Championships, won his heat in 7.70 seconds to go into the final third fastest behind Pozzi, who had equalled his PB and world leading time of 7.44 seconds in his preliminary round, and David Omoregie, who ran 7.69 seconds in his qualifying race.
Omorgie, though, was disqualified from the final, along with Edrin Okoro, for a false start.
All the remaining athletes were cautious at the re-start, with Pozzi clocking 7.51 seconds and King 7.76 seconds in the final.
But both have met the criteria to compete for Great Britain at the Europeans and it is likely Omoregie will join them as he has also run the qualifying time.
Tamar Trotters’ Mike Wilsmore finished ninth in his heat of the 1,500m on Saturday in Sheffield.
Wilsmore clocked 3.58.04, with Bolton’s Tom Lancaster winning the heat in 3:54.49.
Meanwhile, there was joy for City of Plymouth athlete James Arnott at the final Nitro Athletics Meet in Melbourne, Australia.
Representing England, Arnott won his staggered 100m ambulatory race in a time of 11.01 seconds.