Dominic Waldouck made the most of an unexpected call-up and inspired Wasps' return to the top of the Guinness Premiership with a 23-3 win over Worcester.

The England Saxons centre, only included in the side after Steve Kefu was ruled out with a groin injury, played a key role in both Wasps tries.

Serge Betsen touched down in the first half and Tom Varndell rounded off the victory in the last minute with his 50th Premiership try.

Danny Cipriani added 13 points with the boot as Wasps moved back above London rivals Saracens, the only other unbeaten club, on points difference.

Waldouck was named man of the match for a performance that would have caught the eye of England's coaches, who are searching for an inside centre following Riki Flutey's injury.

There was also a welcome return to action for Paul Sackey following the broken leg he suffered during the RBS 6 Nations, though he had little opportunity to press his own Test claims in a stodgy game of few openings.

Waldouck raced on to a pass from Cipriani to carve his way through a giant gap in the Worcester defence.

Chris Latham caught Waldouck with a tap tackle but he popped the ball up for the marauding Betsen, who scored next to the posts and presented Cipriani with a simple conversion.

Varndell then applied the coup de grace in the final minute after Waldouck had launched a counter-attack and then angled his kick infield.

Varndell gathered and had a clear run for the line to score his fifth try in three games since moving from Leicester in the summer.