It was the biggest victory margin that the Saints had ever recorded during the Premier League era.
However, ahead of next weekend's clash against Stoke City at the St Mary's Stadium, Alderweireld has called on his teammates to not get too carried away.
"Of course we can be very satisfied with the result. The second half was much better than the first but we have to keep calm. It is only three points and next week will be tough," BT Sport quotes him as saying.
"We can be happy but from tomorrow we have to be focused on Saturday because it is a big day again. It can change very quickly in the Premier League."
Alderweireld joined Southampton on loan from Spanish champions Atletico Madrid in the summer.