Instead of going around the court to check on Edmund, the tennis pro went up and over the net before helping the British No. 2 tennis player to the sideline.
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.
With British compatriot Andy Murray withdrawing from the first Grand Slam of the year due to his recurring hip injury on Thursday, expectation is growing that Edmund can carry his Brisbane form into the Melbourne showcase.
"In the last two games he wasn't at his best".
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.
While the Canberran has been heavily criticised for his combustible nature in the past, Dimitrov said it was a clear "strategy" and one that was working for him.
"I feel like I'm playing good enough tennis to go deep into ATP-250 tournaments like Brisbane and Sydney".
"I knew the last two games he wasn't at his best so I just had to find a way again", Dimitrov added.
As with his second round match against Matthew Ebden, the Australian focussed his energy, breaking Dolgopolov and wrapping up the second set by 6-3 in 29 minutes. "I probably said it in 2013, and said it probably in 2015, and now I'm saying it again in 2018".
De Minaur will play unseeded American Ryan Harrison for a place in the final.
Edmund had to save two break points in the ninth game of the second set and, encouraged, he swept through the tie-break to deservedly level the match.
Karolina Pliskova kept her title defence on track with a 3-6, 7-5, 6-2 win over 2012 victor Kaia Kanepi, setting up a semifinal against Elina Svitolina.