Nadal, Federer rush to victories in Monte Carlo
Swiss Roger Federer hits a return to Czech Radek Stepanek during the Monte-Carlo ATP Masters Series Tournament tennis match in Monaco on April 16, 2014 - by Valery Hache
Top seed Nadal, champion at eight of the last nine editions, spent 72 minutes in smothering any upset hopes of Russian Teimuraz Gabashvili, who got off to a shock 3-1 lead before Spain's king of clay reeled him in for a 6-4, 6-1 success.
Federer, seeded fourth at a Masters 1000 event that he has never won, delivered a 6-1, 6-2 thrashing to fellow veteran Radek Stepanek.
Federer's rout in 52 minutes was seven minutes longer than another easy victory by holder Novak Djokovic a day earlier.
"I was able to get a lot of returns back into play," said Federer. "On clay, when you have the upper hand from the baseline, it's kind of hard to get out of it.
"I think that's how it was for Radek today. I had a good start to both sets, then I was solid on my own service games.
"The next thing you know, you're in the lead and you can hit freely. It was clearly a good match to start my claycourt campaign."
The Swiss will next face off for a quarter-final spot on Thursday when he takes on Lukas Rosol.
The Czech booked his spot over Frenchman Michael Llodra 6-4, 6-4.
"It's surprising the way he came through, but then again, we know he can play good tennis," Federer said of Rosol, "He's dangerous. He takes big cuts at the ball.
"On clay, on a slower surface, sometimes you get more chances to hit the ball big."
Federer improved to 14-2 over Stepanek, 35, whose last victory in the series came in Rome six years ago.
Federer, 32, swept the first set in 22 minutes and faced his only spot of bother as he saved a pair of break points in the sixth game of the second set.
The winner was aided by five Stepanek double-faults, with Federer breaking four times.
The Swiss won an ATP Tour-leading 25th match of the season.
Nadal steadied after going down early against Gabashvili, with the Spaniard improving to 49-2 at the event. The top seed won six games in a row on his way to claiming the opening set and reaching 4-0 in the second.
A break by his opponent for 4-1 only delayed the inevitable, with Nadal getting the break straight back for 5-1 before taking the win on a first match point a game later.
Nadal will now line up against Andreas Seppi after the Italian defeated Pablo Andujar 7-6 (7/5), 5-7, 6-4.
Australian Open champion and third seed Stanislas Wawrinka was taking on Croatian Marin Cilic.
Canadian eighth seed Milos Raonic duplicated his best showing in the principality with a 6-7 (4/7), 6-2, 6-1 defeat of Taiwan's Yen Lu-Hsun.
Italian tenth seed Fabio Fognini beat Roberto Bautista Agut of Spain 7-6 (8/6), 6-4.