Andy Murray beats Fernando Verdasco at Queen's

Andy Murray won the title at Queen's Club in 2009, 2011 and 2013

Britain's Andy Murray remains on course for a fourth Queen's Club title after a hard-fought win over Fernando Verdasco in round two.

The top seed came through 7-5 6-4 against Spain's world number 42 to reach the quarter-finals of the Aegon Championships.

He goes on to face Luxembourg's Gilles Muller, who beat defending champion Grigor Dimitrov 6-4 7-6 (7-5).

"It was a tricky match," Murray told BBC Sport.

"I was happy with the way I moved. It was a little bit better than the first match."

It was the 28-year-old's 11th win in 12 matches against Verdasco, stretching back to 2007, and their first meeting on grass since the Scot recovered from two sets down to win their Wimbledon quarter-final two years ago.

The 2013 Wimbledon champion appeared in complete command at Queen's Club after Verdasco double-faulted twice in his opening service game, with Murray then thumping away a forehand on break point.

Verdasco got the break back in game seven, however, and the three-time champion was made to toil on a warm afternoon.

A tie-break loomed at 6-5 before Murray was able to take control once again, increasing the pressure and converting his third set point when Verdasco found the net.

The early stages of the second set saw the top seed severely tested on serve, with Verdasco missing a backhand on break point in game one and Murray finding two aces as he recovered from 0-40 in game three.

Murray will face Gilles Muller in the quarter-finals

Verdasco, 31, then snuffed out a fleeting chance for Murray at 2-1 with a forehand down the line and the left-hander held firm until game 10.

Serving to stay in the match, the Spaniard double-faulted twice and saved a match point before, facing a second, he saw two aces ruled out by net cords.

When Verdasco finally made a second serve, Murray attacked with a forehand return and the Spaniard dragged a wayward backhand well over the baseline.

Murray will next face the big-serving Muller, who has hit 56 aces in two matches this week and is coached by the Briton's good friend, Jamie Delgado.

"It may be a bit different," Murray said of seeing his friend on the opposition side.

"Jamie has come to sit in my box and watch matches and stuff and support me.

"I know Gilles very, very well and I like him. We are not extremely close friends but I get on well with him.

"I have played a number of guys like that on the tour, players that I have known since I was very young, and it doesn't change anything for me."

Muller earlier hit 19 aces to knock out Dimitrov, and the Bulgarian sixth seed joined former winner Rafael Nadal and French Open champion Stan Wawrinka as early casualties at Queen's Club.

"I've been coming here for a long time and it was my first time on Centre Court," the 32-year-old, ranked 48th, told BBC Sport.

"It's tough to beat that."

American John Isner beat last year's runner-up Feliciano Lopez of Spain, 7-6 (7-5) 6-7 (9-11) 7-6 (7-4), with Serbian Viktor Troicki knocking out former champion Marin Cilic 6-7 (8-10) 6-2 6-3.