Victoria Azarenka and Sloane Stephens will do their talking on the court as they prepare to meet for the first time since last year's infamous Australian Open semi-final.
Stephens, then a teenager, was playing in her first grand slam semi-final and had just saved five match points to get the second set back on serve.
Azarenka chose that moment to take a long medical time-out before breaking the Stephens serve to clinch victory.
In her on-court interview after the match, Azarenka joked she had nearly committed "the choke of the year", implying the break was tactical.
She later insisted she had been misunderstood and in fact had been struggling with a locked rib that made it difficult for her to breathe.
Azarenka went on to win the final against Li Na to collect her second straight Australian Open crown despite the crowd heavily supporting the Chinese player.
As soon as the draw was made for this year's tournament, a fourth-round rematch was anticipated, but neither player was prepared really to address the subject.
Azarenka, who thrashed Yvonne Meusburger 6-1 6-0, said: "I have great memories of last year. That's all I keep for me.
"Sloane is a great player, a very tough competitor. She has a great record here. I feel like she's improved so much. So I'm excited about the match. It's going to be tough.
"We left it all last year here, and that's what is important for me, is to play another match."
Azarenka has praised the Australian fans at every opportunity, but asked what she could learn from last year, the second seed said: "What is there to learn?
"It was just a great experience for me to be playing in the final and winning the title. That's what I learned, I guess, how to win the second grand slam."
Stephens, 20, has made at least the fourth round at five successive grand slams and booked her place in the second week once more with a 7-5 6-4 win over Elina Svitolina.
On last year's controversy, she said: "That has nothing to do with this year. I don't even remember half the stuff that happened.
"It's a new match. It will be Monday, hopefully on the big court. It will be exciting.
"I know what I have to do. I have to play my game and focus on myself and focus on what I do best."
Elsewhere, Maria Sharapova struggled on but Caroline Wozniacki suffered yet another early exit at a grand slam.
Denmark's former world number one was beaten 4-6 7-5 6-3 by fast-improving young Spaniard Garbine Muguruza.
It meant that for an eighth successive slam Wozniacki has gone out before the quarter-finals, and she has reached the second week just once in that time.
Wozniacki led in the second set, and she said: "Sometimes it happens, you just don't take your chances.
"I don't think I did anything particularly wrong. I thought she played some great tennis as well. It was just a bit unlucky."
Sharapova needed almost three and a half hours to see off Karin Knapp in extreme heat on Thursday, and she wobbled again in the second set against Alize Cornet before pulling through 6-1 7-6 (8/6).
The third seed was so unhappy with her lack of rhythm that she hit the practice courts straight after her match.
Sharapova missed the last three months of 2013 with a shoulder problem, and she said: "I still feel like in certain situations I am a bit rusty and I'm not closing it out when I have to, or maybe going for a little much or over-thinking it a bit.
"That will come. I'm not worried about that. As long as I feel like I'm doing the right things and I'm playing the way I want to play, if I'm making those types of errors, they are going to go in eventually."
Sharapova next plays 20th seed Dominika Cibulkova while Muguruza will face fifth seed Agnieszka Radwanska, who battled past Anastasia Pavlyuchenkova.
Eighth seed Jelena Jankovic and 11th seed Simona Halep were both straight-sets winners and will play each other in the last 16.
The fourth round begins on Sunday, with world number one Serena Williams facing Ana Ivanovic while fourth seed Li takes on Ekaterina Makarova.