London Welsh edged a step nearer their dream of Premiership rugby as they opened up a 13-3 first-leg lead in their Championship play-off semi-final against Bedford at Goldington Road.
Exiles centre Hudson Tonga'uiha ran in the game's only try as the visitors opened up a 13-0 first-half lead.
Full-back Alex Davies kicked the goal, as well as adding two penalties.
But all the home side had to offer was a second-half penalty by skipper James Pritchard.
The second leg is at the Old Deer Park on Sunday week (13 May, 1500 BST).
Cornish Pirates host Bristol at Mennaye Field on Monday (1205 BST) in this season's other Championship semi-final first leg.
FRIDAY NIGHT'S LINE-UPS
Bedford: Pritchard; Dodge, Burke, Staff, Bassett; Sharp, Baldwin; Reeves, Locke, Cooper; Tupai, Howard; Rae, Fox, Barrell.
Replacements: Cochrane, Walsh, Boulton, Fisher, Harding, Veenendaal, Lennard.
London Welsh: Davies; Scott, J Lewis, Tonga'uiha, Ajuwa; Ross, Winter-Moates; Moss, George, Tideswell, A Brown, Corker,
Replacements: Ma'asi, Pittman, Bateman, G Johnson, Beach, R Lewis, Jewell.
Referee: Sean Davey (RFU).