Rafael Nadal returned to the grand slam big-time by weathering a furious Gael Monfils fightback to win 6-3 6-3 4-6 6-4 and reach the Australian Open quarter-finals.
Former champion Nadal had not reached the last eight in a major since the 2015 French Open, so he celebrated wildly after closing out the two-hour 56-minute clash at a packed Rod Laver Arena.
It was not the most convincing of wins for the 30-year-old Spaniard, who became rattled when sixth seed Monfils rallied brilliantly in the third set and went up 4-2 in the fourth.
But Nadal summoned the resilience of his halcyon days to win four straight games and keep his pursuit of a 15th grand slam title alive.
Novak Djokovic may be absent after his shock second-round elimination but third seed Milos Raonic looms as a massive roadblock to Nadal's hopes of a first grand slam semi-final since winning his last French Open in 2014.
"For me, it means a lot because I really start the season playing quarter-finals in a grand slam again, especially on a hard court (and) after a couple of years without being in this round is great news," ninth seed Nadal told reporters, still bathed in sweat after his work on a muggy evening.
"Very happy with an important victory against a very good opponent.
"When you lost the third (set), you are down 4-2 in the fourth, you are not under control, no. That's the real thing."
Monfils came into the match with a 12-2 losing record against Nadal and the flamboyant Frenchman started as if weighed down by the history.
He was broken early in each of the first two sets and made his plight worse with some bizarre shots and mystifying decision-making.
He hammered a pair of blazing winners to save set points in the second set but threw it away with a dismal drop shot.
Nadal appeared on course to coast to a comfortable win but he came unstuck at 4-4 in the third set, double-faulting to hand Monfils a free point then pounding a forehand over the baseline.
Monfils clinched the set with a blazing forehand winner and strutted back to his chair with an index finger pointed at his temple.
Saving two break points and survived a marathon fourth game, an inspired Monfils pounding away at Nadal's serve like a heavyweight boxer.
Nadal fired back with interest and it took a low blow for him to be broken when an unlucky net cord gave him no chance.
The Spaniard leapt to his feet to break back in the eighth game, however, pulling Monfils wide across court before slamming a two-hand backhand into the vacant corner to level at 4-4.
The roar from the crowd almost lifted the stadium's closed roof and Nadal jumped high and pumped his fist in triumph.
The moment felt like a turning-point and so it proved.
Monfils promptly crumbled on serve, bowing out on the second match point with a huge backhand that flew just wide of the line.