Andy Murray overcomes Ivo Karlovic to book place in Wimbledon quarter finals
Andy Murray furthered his reputation as one of the sharpest returners in the game as the Scot overcame Ivo Karlovic's demon serve to book his place in the Wimbledon quarter-finals.
Karlovic's 136 aces put him top of the tournament leaderboard at the start of play but while the 6ft 11in Croatian added another 29 to his tally, precision won over power as Murray sealed 7-6 (9/7) 6-4 5-7 6-4 victory.
A place in the semi-finals rests on Murray beating Canada's Vasek Pospisil, who knocked out Britain's James Ward in round three and Viktor Troicki on Monday.
Murray has never lost to Karlovic in five previous meetings but seven of their 14 previous sets had gone to tie-breaks and the 28-year-old had to win another to pull ahead on Centre Court.
The 6ft 11in Croatian has not been past the quarter-finals at SW19 but he knocked out two-time Wimbledon semi-finalist Jo-Wilfried Tsonga in round three and remains a daunting opponent on grass.
It was a contest of serve-king versus top-returner, with Karlovic leading the tournament rankings on 136 aces while Murray's record of winning 40 per cent of points against opponents' first serve was also the best in the competition.
The British number one predicted his opportunities to crack Karlovic's serve would be few and far between but a break point arrived in the very first game as Murray looked to catch his opponent cold.
The chance went begging, however, and Karlovic, to a chorus of gasps and whistles from the Wimbledon crowd, made his mark with two aces and a 134mph serve.
Between the Croatian's mighty deliveries, one of which clocked a helpless line judge on the head, Murray was able to dictate the rallies and the Scot was frustrated by almost any point he lost which lasted longer than two shots.
Three more break point opportunities came just at the right time for Murray as he led 5-4 and then 6-5, but on each occasion Karlovic served his way out of trouble to force the tie-break.
The Croatian assumed a commanding position when he pulled 4-2 clear but Murray came storming back and after 57 minutes, he converted his sixth set point at 8-7 when a Karlovic forehand flew long.
Buoyed by his advantage, Murray began to loosen up and some brilliant returning gave him an instant break in the second set as Karlovic began to flounder in the face of his opponent's superior shot-making.
Two more break points came and went for Murray in the seventh game, but Karlovic rarely threatened, and the Scot served out to love to clinch the second set 6-4.
Karlovic had the chance to spark a revival when he earned a break point at 2-2 in the third but he failed to convert a simple smash and Murray survived.
The 36-year-old refused to lie down, however, and his chip and charge tactics kept the pressure on Murray, who was forced to serve for a tie-break as he trailed 6-5.
A broken string from a first serve created a delay in play at 30-30 and Karlovic pounced, winning a break point and then sealing the set 7-5 as Murray hit a sloppy backhand into the net.
Centre Court fell flat at the prospect of another set of boom-and-bust but Murray maintained his composure and in the seventh game seized the crucial break.
The Briton did brilliantly to retrieve another thundering Karlovic serve but the Croatian's volley looked to have caught the line before, to the surprise of both players, an optimistic challenge fell in Murray's favour.
The Scot had a break point to win the match at 5-4 but while Karlovic dug deep to hold one more time, he could not prevent his opponent serving out and sealing an 18th consecutive grand slam quarter-final.