Robin van Persie and Danny Welbeck both scored two goals to clinch the win at the Liberty Stadium, ensuring victory for the reigning champions, and Giggs says it can be taken as a message to those questioning United's ability to retain the crown.
"The players don't take any notice of where people expect us to finish. I got told last week that we were third favourites, but we know the quality we have got in the club," the Welshman told MUTV. "We can improve on today's performance, and we will need to. But don't underestimate the result. To come to Swansea and win first and foremost, then to score four goals, is something special.
"Individually and as a team we can get better. The players know that, we're not getting too excited as we know it's only the first game of the season. We can improve and we have to."
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