Kessler retired from the match while trailing 6-1 3-0 after a brief chat with the WTA trainer, but it was clear from the first point to the last that Raducanu had far too much power for her.
Powering service returns with brutal brilliance, this display was a reminder of the kind of form Raducanu served up to win the 2021 US Open, with the confidence flowing for the 22-year-old Brit.
She offered up words of comfort for her opponent after the match, as the American audience in Miami appreciated her comments for her beaten American rival.
"It's never a way any athlete wants to win a match. I wish McCartney a speedy recovery," said Raducanu in her on-court interview.
"She's in such good form right now. Playing so well. Playing so aggressive. We both had long last matches and, yeah, it's a tough physical sport. I wish her all the best."