Rafael Nadal extended his unbeaten run at the Monte Carlo Masters to 34 matches as he reached the last eight with a solid win over Richard Gasquet.
Nadal was rarely threatened and two breaks in the first set and two in the second gave him a 6-2 6-4 win.
He will now play Ivan Ljubicic, who beat fifth seed Tomas Berdych 6-4 6-2.
Second seed Roger Federer beat Marin Cilic 6-4 6-3 and next faces seventh seed Jurgen Melzer, who was a surprise 6-1 6-4 winner over Nicolas Almagro.
World number one Nadal said he was "very happy" with his form against Gasquet.
"I think I played better than yesterday, easier. In general, I think it was a very positive victory against a very difficult opponent," Nadal continued.
"I feel when I'm playing well with the forehand, it is a very important shot for me, so I can have the control of the point most of the time.
"When I am playing well with the forehand, everything is a little bit less difficult."
After breaking in the first game of the match, Nadal found his first service game a tricky affair. However, after fighting off several deuces, he duly held and, even at that early stage, there was only going to be one winner.
France's Gasquet tried to be aggressive and produced some good shots but his opponent was a class apart and a second break at 4-2 helped Nadal take the first set in 44 minutes.
The Spaniard dropped only six points on his serve in the opening set and was equally in control for much of the second.
Gasquet fought off a break point at 2-2 with the help of three big serves in a row and continued to try to take the game to Nadal with some brave shot making.
But, in his next service game, he found himself facing two break points and, although he saved the first, a looping forehand on the run that just clipped the baseline gave Nadal a 4-3 lead.
It looked like being decisive but Gasquet was in no mood to lie down and after forcing a break point, a running forehand pass resulted in him drawing level at 4-4.
However, Nadal immediately earned two break points of his own and duly broke back before serving out to reach the last eight.
Federer cruised through his early service games but, although Croat Cilic struggled to get his first delivery in play, the world number three found it difficult to get to grips with his 6ft 6in opponent's high kicking second serve.
It looked as though the first set was headed for a tie-break but at 5-4 Cilic's steady form suddenly deserted him and a series of errors handed the break and the set to Federer.
The second set soon settled into a similar pattern as the first with service dominating until the sixth game, when Federer secured the decisive break with a fizzing backhand pass.
A couple of Federer errors resulted in him taken to deuce on his serve in the next game but the Swiss star refocused and eased into the last eight with no further alarms.
"Today was another solid performance, which I'm very happy about," Federer reflected. "I think I was consistent and didn't allow him to get into the points he wanted to on my own serve.
"The first set was close until he had that loose game. He can be dangerous, so I'm pleased to go through."
Fourth seed David Ferrer reached the quarter-finals with a 6-1 6-3 win over Milos Raonic but fellow Spaniard Tommy Robredo was leading Viktor Troicki 6-3 1-2 when forced to withdraw through injury.
There was another surprise when Portugal's world number 82 Frederico Gil beat French eighth seed Gael Monfils 7-6 (8-6) 6-2 to set up a quarter-final