Dimitrov was the first to come to his aid, leaping the net and sprinting over to help his opponent up and guide him to his chair.
Ranked 50th in the world, Edmund is looking to right the wrongs of last year's Australian Open when he suffered a straight sets second round defeat to Spaniard Pablo Carreno Busta. "At the end of the day, health above all", Dimitrov said immediately afterwards.
The Ukrainian battled back from 4-0 down to claim the opening set before needing four match points in the second to secure the win.
Edmund went down crying in agony after what appeared to be an innocuous movement with Dimitrov serving at 4-4 in the third set. "It's very unfortunate what happened, for sure".
Harrison had been due to face Andy Murray in the second round but after avoiding the Scot, who withdrew from both Brisbane and the Australian Open with his ongoing hip injury, and will now get a shot of reaching the final. "I just had to find a way again".More news: Liverpool stand firm as Barça advertise Coutinho shirts
"The only positive I can say about losing that first set (against Dolgopolov) is I'm putting myself in some pressure situations and getting some more court time out there which is good".
"The first match of the year and I get to play two-and-a-half hours", he said. "I played some pretty good tennis in the second and third sets".
"The body feels good and the game feels good". The 18-year-old de Minaur stunned fourth seed Milos Raonic in the second round and there was no letdown Friday as he ousted U.S. qualifier Michael Mmoh 6-4, 6-0 to reach his first ATP semi-final.
He was able to resume but went on to lose 6-3 6-7 (3-7) 6-4.