MELBOURNE - It's the new order up against the old guard in Wednesday's men's quarter-finals at the Australian Open with Kei Nishikori facing defending champion Stan Wawrinka and Milos Raonic trading shots with Novak Djokovic.
Serbia's Novak Djokovic celebrates after victory in his men's singles match against Luxembourg's Gilles Muller during the Australian Open tournament in Melbourne, on January 26, 2015
Much has been made about the generational advance of the younger breed in the Grand Slams and the tennis world will get an insight into whether that is indeed the case in these intriguing match-ups on Rod Laver Arena.
Japanese superstar Nishikori ousted Raonic, Wawrinka and Djokovic on the way to losing to Marin Cilic in last year's US Open final when he became the first Asian man to contest a Grand Slam decider.
Big-serving Canadian Raonic hasn't beaten world number one and tournament favourite Djokovic in four meetings, but he has been serving up a storm in Melbourne over the past week.
Djokovic has looked the player to beat and has yet to drop a set on the way to the last eight as he chases his fifth Australian title and eighth Grand Slam.
Raonic, 24, and Nishikori, 25, will be bidding to prevent a Djokovic-Wawrinka semi-final in the top half of the men's draw.
"I know what to expect. We practice a lot. We live in the same place (Monte Carlo). We're good friends," Djokovic said of meeting Raonic.
"He's very confident. He's been playing some great tennis in the last 15 months. He deserves to be where he is now in the top 10 and coming closer to top five in the world."
Djokovic, however, is supremely confident.
"I haven't dropped a set, I'm in the quarter-finals. Yes, I had tough matches in the last two rounds, but I had quality opponents.
"I've dropped serve only once during the whole tournament. That is very encouraging. Overall it's a positive feeling going into the quarters."
Raonic, who became the first Canadian man to reach the Australian quarters in 47 years with his five-set win over Feliciano Lopez, is leading the tournament with 99 aces and has the highest first-serving percentage of 72 from his first four matches.
"I'm moving better. I feel like I have it within myself. I've just got to bring it out. I'm going to focus on myself first, make sure that I get my things in order, get my things organised, play my game," Raonic said.
- Tough, tough player -
Wawrinka, who upset Djokovic in the quarters on the way to beating Rafael Nadal in last year's final, has dropped only one set in reaching the last eight.
But his biggest test so far awaits against fifth seeded Nishikori.
"I'm happy with the way I'm playing. My game is there. I haven't spent too much energy on the court in the first week," the Swiss said.
"Kei's a tough, tough player. He improved a lot last year. He's a great shotmaker. He can make winners, he always takes the ball early. It's always tough to play against him. He doesn't give you a lot of time."
Nishikori made surprisingly easy work in disposing of Spanish terrier David Ferrer in straight sets to advance to his third Grand Slam quarter-final.
The Japanese star has a losing 1-2 record against Wawrinka, but has looked the part in Melbourne, buoyed by his performances at the US Open.
"It's going to be a really tough match. He can hit forehands, backhands -- a great backhand actually. He can hit anywhere on the court, even from the back," he said.
"I am feeling a lot of confidence. I've been playing well. It's going to be an exciting match."