Last weekend, as Swansea were losing 4-2 at Stamford Bridge, Southampton were comfortably beating Newcastle United 4-0 at St Mary's Stadium.
Ronald Koeman's side produced a slick passing display and were lethal in front of goal to punish Alan Pardew's men, something Sigurdsson is wary of ahead of their meeting at the Liberty Stadium on Saturday.
However, the Iceland international is confident Garry Monk's side will quickly recover from their disappointment last weekend and bring the visitors' recent good run to an end.
"It's been a great start for the team and myself, we can be really pleased with having nine points from four games," he told the club's official website.
"Southampton were very impressive last time out. They beat Newcastle 4-0 and really showed how dangerous they can be.
"They have really done well considering the players they lost in the summer and, of course, a change in manager.
"But we have had a similar situation here, and we have also done very well.
"They are only a point behind us, but hopefully we can open that gap to four points and continue our excellent form in front of our fans."
Swansea fell to defeat in both matches against Southampton last season and are looking for their first Premier League victory over the south coast club.
