London Wasps moved closer to clinching a home match in the quarter-finals of the Amlin Challenge Cup after a 20-19 win over the Newport Gwent Dragons.

The Londoners were already assured of a quarter-final place but were eager to improve their ranking for the next round by completing the double over Darren Edwards' Dragons, who lost 38-25 at Adams Park.

Tom Prydie's first of three penalties opened the scoring for the Dragons, but Nick Robinson levelled the score with his boot with 21 minutes played.

Daniel Evans scored Newport's only try of the game on 26 minutes, which was converted by Prydie, although the visitors had a penalty try before half-time.

Robinson's 57th-minute try opened up a four-point lead with 20 minutes to go and while Steffan Jones kicked a three-pointer late on the Aviva Premiership held on for a slender success.

Tom Prydie opened the scoring with a 16th-minute penalty but Wasps were soon level as Nick Robinson added three points five minutes later.

Dan Evans was first to get over the line, despite the attentions of flanker Sam Jones, Prydie converting to give the Dragons a 10-3 lead in the 26th minute.

But Robinson added three more penalty points before ensuring Wasps took the lead in the 36th minute, the Wales fly-half adding the extras following a

penalty try award.

Prydie levelled on the stroke of half-time and kicked the hosts ahead in the 52nd minute but Dai Young's men were not ready to give up.

Five minutes later, Robinson collected his own grubber to dot down for the first time before making sure of the conversion.

A period of attrition followed, with Prydie missing a penalty, but replacement Steffan Jones would narrow the deficit to a single point with six minutes to play.