The Scottish side ran out 25-13 winners when the sides met at BT Murrayfield last weekend, maintaining their 100 per cent record in the competition. The two teams meet again at the Kassam Stadium on Sunday, with London Welsh searching for their first win of the season. But Scotland flanker Grant expects the Pro12 outfit to be on better form as they look to take another step towards a place in the quarter-finals. “We are our own biggest critics and we know it wasn't good enough. The first half was certainly very sloppy,” said Grant. “We lost so many balls during that first half, the breakdown was messy and we lost the ball in contact. On the plus set out set-piece was better than it had been, we had taken a lot of stick for that and it was justified. “It wasn't a polished performance but it was a lot better and it is something to build on. If you have a good set-piece it makes the game of rugby a lot easier. “We now get another shot to improve our performance, which is great and we want to make sure we are better this week.” But Exiles fly-half Gordon Ross is similarly confident that Justin Burnell's men will be all the better for having had the chance to weigh up the strengths and weaknesses of their opponents. He said: “We were a bit one-dimensional last week and could not play to our strengths. We will have a look at the performance and see what we can do to combat a physical and well-drilled Edinburgh team.” Match Facts ? London Welsh have lost their last four games in the Challenge up, whilst Edinburgh have won their last four; this represents the best and worst form in for these two clubs in the competition, respectively. ? Edinburgh Rugby's win against London Welsh was their first victory in three attempts against an English side; they are yet to win on English soil however. ? In Edinburgh's Challenge Cup history, no player has managed to score more than one try in a single game in the competition for the Scottish side.