Ronald Koeman believes that Southampton keeping consecutive clean sheets following their 1-0 win over Sunderland displays their progression from last season.
In an impressive campaign last term, Southampton finished seventh in the Premier League and qualified for European competition.
Dusan Tadic's penalty secured victory over Sunderland on Saturday, sending Koeman's side up to the same position and keeping them unbeaten on the road in the top-flight this term.
But the Dutchman was happiest with the fact they have kept back-to-back clean sheets for the second time this season, believing that shows improvement from their previous campaign.
"The penalty was well taken by Dusan and that brings three points and the second clean sheet in a row, still unbeaten away from home - I think that's fantastic," Koeman told Sky Sports.
"We have experience from last year, you need wins and clean sheets but the second in a row is the difference compared to last season.
"In my opinion it's a key point to finally reach a high position in the table."
Koeman was impressed by his side's display at the Stadium of Light but hopes they can improve in the final third next time out.
"I think we played well. It was difficult against the good organisation of Sunderland," he added.
"We had good pressing and this result is well deserved.
"It's difficult to create and maybe we were not that clinical in the box - not so good in our final pass."
