Russian Medvedev, who had been booed for his prank on Fritz, put his fingers in his ears after confirming his victory over De Minaur.
He lost just nine points on serve as he won in one hour and 18 minutes.
“I went into this match blocking out the noise, even from myself,” said Medvedev, 28, the 2020 champion.
“I didn’t really care what was happening on the court, I just tried to play and it felt good.”
Medvedev’s temperament came under scrutiny after his wild behavior 48 hours earlier, but he struck the ball brilliantly and broke in the third game with a cross-court winner.
He earned a double break when De Mino double-faulted and took the first set in 40 minutes.
De Minaur, 25, had a close second set but held serve to win after a stunning backhand from Medvedev took him 5-4 up.
In doubles, Patten and Heliovaara beat Australia’s Max Purcell and Jordan Thompson 7-6 (7-3) 7-5 to reach the Wimbledon final.
The British-Finnish duo are bidding to become the first team to win the Wimbledon and ATP Finals trophies in the same season since Mike Bryan and Jack Sock in 2018.
