"It was frustrating against Stoke but we have to look forward. In a season you will have games like that. It was a good performance, we just forgot to score goals and on another day it could have been three or four nil. It just didn't happen for us," said the Dutch international.
"You can always look back at games but I think it's better to instead look forward to our next match at Everton. If we win on Saturday we'll have made a really good start to the season. We'd have beaten Manchester United and enjoyed other good results home and away. A lot of positive things have happened so far this season so there's nothing gained by being negative.
"We wanted a good start to the season and so far we've had one. Now we have to keep going and keep winning games."