Gloucester 32 Wasps 37: Wasps nip the early spring of Lamb

Wasps, the artful dodgers of the Premiership, picked another pocket or three yesterday with one of their most audacious scams yet. In a spellbinding encounter the defending champions survived a magical spell by glorious Gloucester before producing the sting in the final quarter. Their reward is a semi-final at Sale on Sunday - the other is between Leicester and London Irish - with the winners going to Twickenham on 27 May.

If it wasn't daylight robbery, Wasps certainly lived dangerously and at one point looked as if they were going to be run off their feet by a side who scored some of the most spectacular tries ever witnessed at Castle Grim.

Kingsholm has always been so described because it was as far removed from a bouncy castle as can be imagined. Historically the emphasis was on forward power and a stand-off who did almost nothing but kick. How does a leopard change its spots? Introduce a Lamb into the fold.

Ryan Lamb, an England Under-19 and Under-21 No 10, swept Gloucester into what appeared to be a commanding lead. "We go out to play," Lamb, who will be 20 later this month, said, "but in the last 10 minutes Wasps were a bit smarter."

In the 68th minute, when Gloucester were clinging on to the lead, Dean Ryan, their coach, replaced Lamb with Ludovic Mercier. It was a safety-first measure which backfired.

"We were struggling for field position," said Ryan. Field position doesn't appear to mean much to Lamb, whose sense of adventure enabled Gloucester to turn the match on its head.

However, there was another somersault when Wasps turned 32-20 into 32-37. Wasps have won the last three championships not by finishing top of the table at the end of the regular season but by, in succession, mugging Gloucester, Bath and Leicester at Twickenham. "You don't become champions three years running without having fighting spirit," Lawrence Dallaglio said. The Wasps captain was making his 150th appearance in the Premiership and at times it showed.

Gloucester got off to a cracking start when Anthony Allen took a short pass at pace and scorched through a gap left by Josh Lewsey, who had drifted right, and skipped past Tom Voyce's fragile challenge to go over near the posts. Lamb missed the conversion but it couldn't have been down to nerves. At that age they don't exist.

Wasps' response appeared deadly as they racked up 20 points in 16 minutes. Mark van Gisbergen, back to his best form - it was only when England picked him that he went into his shell - knocked over a couple of penalties before launching a counter-attack that ended with Joe Worsley muscling past Peter Richards, Mark Foster and Alex Brown.

The full-back was not finished. Appearing on the left wing, he wrong footed four defenders to round off a multi-phase move and his conversion gave Wasps a 15-point lead.

However, Lamb kicked a penalty just before the break and was then quite sensational in the opening minutes of the second half. His clever chip beat the blitz defence for Allen to score at the posts. From the re-start, Lamb threw out a long pass to James Simpson-Daniel, who had moved into the centre in place of Mike Tindall, and he spreadeagled the defence. When Lamb regained possession he sold a dummy which was bought by Worsley and had the pace to elude Stuart Abbott. 22-20.

When Worsley was sent to the bin for pulling back Alex Brown, Lamb landed the penalty and by the 58th minute Gloucester had extended their lead to 32-20. Withstanding a sustained assault, Lamb suddenly delivered a huge pass to his right, where Simpson-Daniel was up against Dallaglio and Simon Shaw. The forwards stood no chance and the flying hyphen gave a scoring pass to James Bailey. Lamb converted from the touchline.

Kingsholm was in the land of milk and honey. This time last season the stand-off was playing for Pertemps Bees. Here he was the bee's knees, until Ryan took him off.

However, the Gloucester coach had described Wasps as the "best team in the world at knock-out rugby" and he was not far wrong. First Van Gisbergen kicked a penalty and then Paul Sackey came in off his wing to touch down at the posts.

In the 74th minute Voyce made inroads and found the outstanding Worsley on his inside. The England flanker had the speed to make it to the line from 30 yards out. On any other day he would have been man of the match, but this menu had Lamb written all over it.

Gloucester: O Morgan; J Simpson-Daniel, M Tindall (J Bailey, 40), A Allen, M Foster; R Lamb (L Mercier, 68), P Richards (H Thomas, 40); P Collazo (T Sigley, 71), M Davies (O Azam, 68), J Forster, J Pendlebury (A Eustace, 68), A Brown, P Buxton (capt), J Forrester (L Narraway, 68), A Hazell.

Wasps: M van Gisbergen; P Sackey, J Lewsey, S Abbott (F Waters, 72), T Voyce; J Staunton, E Reddan (J Honeyben, 78); T Payne, J Ward, P Bracken (J Va'a, 72), S Shaw, R Birkett, D Leo, L Dallaglio (capt), J Worsley.

Referee: T Spreadbury (Somerset).