Younes Kaboul has stressed the need for us not to get carried away after our double London derby success last week.
Back-to-back wins against Arsenal and Chelsea left everyone on a high, but the season is far from over - and neither is the race for fourth place.
We overtook main rivals Manchester City to gain pole position on Saturday after their own derby defeat to United - who we take on at Old Trafford this weekend.
But defender Younes, who impressed in an unfamiliar right-back role during the two wins, knows we still face a fight to hang on to the coveted Champions League spot.
He said: "It was a big week for us and I don't think many people would have seen us beating Arsenal and Chelsea after we lost against Portsmouth in the FA Cup semi-final.
"I hope we build on these results this weekend. It will be a very hard game at United next Saturday but we can get a result up there, why not? It's only about us.
"We have to keep concentrating until the end of the season because it's not finished. We've done well, but we've got to put that behind us and keep going.
"City losing at the weekend was good for us, and if we keep playing like we have done over the last two games, there is no reason why we shouldn't finish in fourth place."