Edinburgh made it four wins from four as they battled to a 24-6 win over London Welsh thanks to tries from Dougie Fife and Roddy Grant.
It was tight for much of the game, with Edinburgh leading 9-3 at half-time thanks to three penalties from Sam Hidalgo-Clyne.
Chris Elder slotted one penalty for Welsh, but they lost Lachlan McCaffrey to a sin-bin on the stroke of half-time, having failed to take advantage of a yellow card for Andries Strauss earlier in the half.
Hidalgo-Clyne and Elder exchanged penalties early in the second half, but it was still very tight with half an hour to go.
Eventually Edinburgh did find a way through, with Jack Cuthbert feeding Fife for the game’s first try.
That gave Edinburgh a 17-6 lead, and after Dean Schofield’s sin-binning with three minutes remaining, Grant sealed the win in the dying seconds.
For London Welsh:
Pens: Elder 2
Yellow Cards: McCaffrey, Schofield
Tries: Fife, Grant
Pens: Hidalgo-Clyne 4
Yellow Card: Strauss
London Welsh: 15 Elliot Kear, 14 Chris Elder, 13 Alan Awcock, 12 Tom May (c), 11 Nick Scott, 10 Olly Barkley, 9 Rob Lewis, 8 Lachlan McCaffrey, 7 Carl Kirwin, 6 Peter Browne, 5 James Down, 4 Dean Schofield, 3 Taione Vea, 2 Nathan Morris, 1 Eddie Aholelei.
Replacements:16 Nathan Vella, 17 Ricky Reeves, 18 Ben Cooper, 19 Matt Corker, 20 Ben Pienaar, 21 Paul Rowley, 22 Piri Weepu, 23 Nick Reynolds
Edinburgh: 15 Jack Cuthbert, 14 Dougie Fife, 13 Matt Scott, 12 Andries Strauss, 11 Tim Visser, 10 Greig Tonks, 9 Sam Hidalgo-Clyne, 8 Mike Coman (c), 7 Roddy Grant, 6 Tomas Leonardi, 5 Ben Toolis, 4 Anton Bresler, 3 John Andress, 2 Neil Cochrane, 1 Rory Sutherland.
Replacements:16 James Hilterbrand, 17 Grant Shiells, 18 WP Nel, 19 Fraser McKenzie, 20 Stuart McInally, 21 Grayson Hart, 22 Tom Heathcote, 23 Sam Beard
Referee: Alexandre Ruiz