Federer advanced to the Miami Open final with a dramatic win against Nick Kyrgios that went three tiebreakers.
Nadal had a much easier time in taking down Fabio Fognini 6-1, 7-5.
On Sunday, they'll meet for the championship (1 p.m. ET on ESPN & the ESPN App). Will it be an instant classic?
Their rivalry, considered one of the greatest in tennis history, has produced some memorable matches over the years. Here are the top five:
1. Wimbledon final, 2008
This Federer-Nadal meeting on the famous grass courts at Wimbledon had it all.
Federer was chasing a sixth consecutive Wimbledon title while Nadal was trying to emulate Bjorn Borg's French Open-Wimbledon double in 1980.
Nadal made the better start and won the first two sets before rain intervened. The 80-minute stoppage disrupted the Spaniard's momentum as Federer came roaring back to win the third and fourth sets.
Federer was within two points of victory in the decider, but Nadal held his nerve to prevail 6-4, 6-4, 6-7(5), 6-7(8), 9-7 in the London darkness.
After the match, tennis legend John McEnroe was quoted as saying: "This is the greatest match I've ever seen."
2. Australian Open final, 2009
Tennis fans didn't have to wait too much longer for another Nadal-Feder epic. And with these two, there always seems to have been landmarks on the line.
Nadal, who was ranked No. 1 at the time, was on course to become the first Spanish man to win the Australian Open, while Federer had the opportunity to equal Pete Sampras' all-time record of 14 Grand Slam titles.
Nadal defeated Federer over five sets -- 7-5, 3-6, 7-6(3), 3-6, 6-2.
3. Australian Open final, 2017
When no one thought they'd see Federer and Nadal meet in a Grand Slam final again, the pair defied expectations to secure an Australian Open final showdown.
In the twilight of their careers, a lot seemed to be at stake beyond the obvious. Federer had not won a Grand Slam final since Wimbledon in 2012, and Nadal's dry spell dated to 2014 at Roland Garros.
Federer had the last laugh this time, running out a 6-4, 3-6, 6-1, 3-6, 6-3 winner.
4. Rome final, 2006
One of their closest meetings on clay, Nadal prevailed after teetering on the brink of defeat; it was his 16th title as a teenager.
The Spaniard was down 4-2 in the fifth set and saved two match points before he triumphed 6-7(0), 7-6(5), 6-4, 2-6, 7-6(5) in a classic encounter that lasted more than five hours.
The victory put Nadal very much in the ascendancy in their rivalry, it being his fifth victory in six matches against the Swiss.
5. NASDAQ-1OO Open final, 2005
Federer and Nadal had met once before this, but this was the pair's first meeting in an ATP Tour final.
Nadal was 18 years old at the time and introduced himself to Federer -- who had won the Australian Open, Wimbledon and the US Open in 2004 -- by taking the first two sets.
However, it wasn't to be for Nadal this time as Federer fought back to win 2-6, 6-7(4), 7-6(5), 6-3, 6-1.