At 4-4 in the third set, Edmund tumbled to the court, clutching his right ankle with both hands.
His opponent, realising how serious it could be, vaulted the net to aid his stricken opponent, later helping Edmund limp to his chair for treatment.
Dimitrov finished 2017 as the form player on the ATP tour and seems to have carried that momentum into the new season, having held off a ferocious challenge from Aussie underdog John Millman in the second round before another hard tangle with Edmund.
The quarterfinal field was wrapped up at the Brisbane International on Thursday, but not before the defending champion very almost joined six other seeded players on the sidelines. The two squared off previous year in Washington where the world No. 3 earned a hard fought three-set victory over the British No. 2.
Dimitrov will now play mercurial Australian Nick Kyrgios in a blockbuster semi-final.
Dimitrov held his serve to go to 5-4 and then broke Edmund to seal the win 6-3, 6-7 (3/7), 6-4.
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Morgan, however, insisted that he brought out the doll for a "genuine education", and asked, "How does your physique compare now". Kim now wished that her stepmom, Cait, would just shut up and stop bashing her family everytime she gets the chance of doing so.
"At the end of the day it's health above all", said Dimitrov.
"I will look to fly to Sydney and I'm ready to pick myself up and go again, " he said. I played aggressive tennis and got rewarded for that. Istomin advanced 7-6 (5), 6-2 over Jared Donaldson and Harrison had a 6-7 (5), 6-4, 6-2 win over Yannick Hanfmann, who was a late addition to the draw after Andy Murray withdrew. I was just kind of focusing on the most important thing, like, recovery, getting back into the court, like, slowly getting the rhythm in again.
The other final four clash sees Ryan Harrison face teenager Alex De Minaur.
"The guys sending me messages on Instagram think I could have done more - I got called some pretty nasty names for losing that point, " Millman said.
Sasnovich, who has a career-high ranking of No. 85, will meet either defending champion Karolina Pliskova or No. 3-seeded seed Elina Svitolina in the championship match.
Edmund fell to the ground with the third set tied at 4 and appeared to be in pain.