Novak Djokovic moved into his first quarter-final of 2018 on Thursday when he defeated Spain's Albert Ramos-Vinolas 6-1, 7-5 at the Italian Open.
The four-time Rome champion is making his way back this year after a six-month injury absence before the Australian Open, which was followed by elbow surgery.
And the 30-year-old showed some of his old form as he got past Ramos-Vinolas to set up a rematch with Japan's Kei Nishikori for a semi-final berth.
The 11th-seeded Serb, who has reached eight of the last ten finals in Rome, beat Nishikori in the first round in Madrid last week before falling in the second to Britain's Kyle Edmund.
"I'm happy. I haven't had too many matches of this quality of my tennis in the last 12 months," said the 12-time Grand Slam champion whose last quarter-final run came at Wimbledon last year.
"I think this was probably one of the three matches that I played this way in the last 12 months. So, it felt good.
"And it came at the right time in the place where I love to play, where I get a lot of support.
"I'm just trying to thrive on this energy that I get from people here. I've historically always played well in Rome, and I feel like each match is getting better."
Former world number one Djokovic has slipped six places to 18th after his second-round defeat in Madrid, his lowest ranking since October 2006.
Nishikori, ranked 24, who retired in the second round in Barcelona last month with a leg injury, needed just over an hour to see off Germany's Philipp Kohlschreiber 6-1, 6-2 at the Foro Italico.
"It was great match. I think I played perfect tennis today," said 28-year-old Nishikori.
Djokovic said: "I expect a big fight from both of us. We had some epic matches also here a couple years ago, semi-finals.
"With Kei you know that you're going into a match where balls will come very quick from each part of the court.
"So, I have to be able to start off with the right intensity and try to impose my game, my tactics.
"But it's not going to be easy, because he also likes playing here.
"I saw the result (today) was quite easy. So, he's also in a good form. He's raising his level of tennis.
"So, I think this match tomorrow comes at the right time for both of us to see where we are with our game."
Last-eight spot: Novak Djokovic on his way to victory over Albert Ramos Vinolas on Thursday