Andy Murray takes on Janko Tipsarevic for a place in the semi-finals of the Sony Ericsson Open today, his confidence high and his tail up after one of his best performances of the year so far.

The Scot's 6-3, 6-4 win over Gilles Simon of France last night was an exercise in efficiency, one break in each set enough to see him through to the last eight.

But it will be the manner of the victory that will have pleased coach Ivan Lendl as he watched his man take his win-loss record over the world No 13 to 9-1.

Such was Murray's dominance, he was able to position himself on the court close to the baseline and Simon effectively became a rabbit, running twice as much as Murray throughout a match that only ever looked like going one way.

True, the first game did last 17 minutes and include a 40-stroke rally, but once Murray had held, the psychological advantage soon set in.

World No.4 Murray broke in the fourth game on his way to wrapping up the first set and after missing a few break point chances in the fourth game of the second, he broke for 4-3 and never looked back.

It was an authoritative performance that will have pleased player and coach alike, even if the match-up against Simon – in essence a lesser version of Murray – always plays into the Scot's favour.

Murray will need to be on similarly top form against Serbia's Tipsarevic, who has cemented his place in the world's top 10 this year.

The pair have met seven times before, with Murray winning four of them, including their last clash at Queen's Club last summer.

But the Serb always raises his game against the very best players and Murray will not need reminding what happened in Dubai two years ago, when he lost in three sets and was later accused of not giving his all after admitting he was trying out a few things.

Should Murray get past Tipsarevic, the chances are he will face Rafael Nadal in the semi-finals but the world No 2 gave his supporters some cause for concern when he had both knees strapped during his fourth-round clash with Kei Nishikori of Japan.

It didn't stop him from winning through 6-4, 6-4 but Nadal has had so many problems with his knees over the years that with the clay-court season just around the corner, he will be hoping it was just a twinge and nothing more.

"I was not probably in perfect condition today with the knee, but the important thing is to try to win as many matches as possible," Nadal said.

"For me here is an important tournament and every victory has a very, very big value for me. Then after this, I have two weeks to recover for Monte Carlo."

Top seed Novak Djokovic made routine progress into the last eight with a straight-sets win over Richard Gasquet. The Serb served six aces and broke serve three times to record a 7-5, 6-3 win over the 17th seed and set up a quarter-final against Juan Martin Del Potro or David Ferrer.

Eighth seed Mardy Fish beat Nicolas Almagro 6-3, 6-7 (2/7), 6-3 in two hours and 36 minutes.

In the first of the women's quarter-finals, second seed Maria Sharapova hammered China's Li Na 6-3, 6-0 in an hour and nine minutes in a match containing neither an ace nor a double fault.

It is the fourth time Sharapova has reached the semi-finals at this tournament but represents her first win – and, indeed, the first time she has even won a set – in five meetings with Li.

"I came into this match losing to her the last few times. I really wanted to change that," said Sharapova.

"I was really consistent today in conditions where it was a little gusty and blowing around, and I faced a tough opponent too. I did a good job of maintaining my consistency throughout the whole match."