The Red Devils dominated in possession, but failed to look dangerous going forward as captain Wayne Rooney continued his poor form in the Premier League.
However, Van Gaal admits he will not panic buy before the transfer window closes on Tuesday.
It's not the last moment that we panic
Louis van Gaal
When asked if today's result at the Liberty Stadium would influence his summer activity, Van Gaal replied: "No, it does't have any effect.
"When you are scouting players then you know already in advance within a month, two months, you know who you can buy.
"It's not the last moment that we panic. When you see the game you know we are the dominant team."
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