Roddick uses express service to slow Melzer

Andy Roddick wasn't born when "Boom Bang-a-Bang" was written, yet the title of Britain's 1969 Eurovision Song Contest entry perfectly sums up his tennis. The sixth seed served splendidly in his third-round match yesterday, deploying his primary weapon to devastating effect in overcoming the Austrian left-hander Jürgen Melzer 7-6 7-6 4-6 6-3.

Assuming that the top half of the draw now proceeds according to seeding, Roddick will meet Andy Murray in the semi-final on Friday. It will be "C'mon Andy" day.

But Melzer, to cite Monty Python's spoof of "Boom Bang-a-Bang", is himself no "Bing Tiddle-Tiddle-Bong". He unleashed almost as many aces as Roddick, at a lower velocity but with killing accuracy. Both players were aided by the sun-baked hardness of Centre Court, though Roddick made more of it, particularly with his second serve, which on occasion reared up like a Brett Lee bouncer.

Roddick has been a fixture at Wimbledon for years but he is still only 26, surely a little too young to merit Greg Rusedski's observation that "at his age" the American could expect to struggle when required to scurry. After all, Melzer is even more superannuated, at 28. But it was true that in the first two sets, the few extended rallies were mostly won by the Austrian, seeded 26. Roddick didn't have so much as a break point until 4-4 in the second set.

He had won all eight previous encounters with Melzer, seven of them in straight sets, and though they had never met on grass, the American, a finalist here in 2004 and 2005, plainly had a psychological edge.

If Roddick does end up playing Murray in the semi-finals, the contest will bring together the world's best server and the world's best returner. His service action, in truth, is not a thing of beauty, his extraordinary power the result of an exaggerated knee bend like someone preparing to lift a suitcase full of books. But what do aesthetics matter when a man can propel a ball over a net at 137mph? That was Roddick's fastest serve yesterday. His fastest ever, measured at 155mph, is a record.

This match was not just a story of power serving, however, any more than it was just Roddick's story. Melzer had never fought back from two sets down in a five-set match but he battled his way back into the fray with occasionally inspired all-court play, drop-shotting audaciously and conjuring some marvellous disguised lobs. He finally broke the Roddick serve, which must have felt like breaking an iron girder, in the fifth game of the third set, and held on to take the set 6-4.

Roddick continued to look less than comfortable when he wasn't belting serves or firing howitzers from the baseline but he is made of stern stuff. Under the appreciative gaze of his new wife Brooklyn Decker, he broke Melzer twice in the fourth set and despite surrendering a break himself, closed out the match emphatically, winning the first of three match points with yet another ace, his 33rd.

The new Mrs Roddick is a blonde swimwear model for whom he reportedly fell not when their eyes met across a crowded room, but when he clocked her in Sports Illustrated and asked his agent to make contact. The age of romance might be dead, but the age of the massive server goes on.

Elsewhere, the third round yielded two five-set marathons with a lower seed putting out a higher one. The No 24 seed Tommy Haas took four hours, 28 minutes to beat Mario Cilic, seeded 11, 7-5 7-5 1-6 6-7 10-8, while the No 23 seed, Radek Stepanek, prevailed over David Ferrer, seeded 16, winning 7-5 7-5 3-6 4-6 6-4. Stepanek will now play the 2002 champion Lleyton Hewitt, who continued his terrific form, despatching Germany's Philipp Petzschner 7-5 7-6 6-3. The Australian has yet to drop a set.

Fernando Gonzalez, who was a potential quarter-final opponent for Murray and had beaten him at that stage of the French Open, went down in five sets to Spain's Juan Carlos Ferrero.

Jamie Murray, Andy's brother, partnered Liezel Huber to a 7-6 3-6 6-3 victory over Nenad Zimonjic and Zi Yan, the No 10 seeds, in the second round of the mixed doubles.