Sunderland have kept two clean sheets in their last two matches.
The Black Cats leaked goals over the early part of the season, with Dick Advocaat failing to find a way to make the team look very secure.
However, since Allardyce has taken charge Sunderland have made a big improvement in a defensive sense, and Larsson doesn’t believe that their new found solidarity is a coincidence.
The Swedish midfielder says that Sunderland’s squad have worked very hard in training to make themselves a much harder team to break down.
“We needed to start somewhere. That was being a bit more solid,” he said.
“We feel a bit more secure, feel like we’re not giving chances away constantly and worrying about conceding goals.
“That really helps with the confidence.
“It’s the one thing we’ve worked the most on, and then trying to win the game.”
Sunderland started slowly under Allardyce’s regime, and after they conceded six goals against Everton there were concerns over whether the 60-year-old would be able to keep the team up.
However, the Black Cats have now kept two clean-sheets in their last two matches, and they are looking far more organised.
Wins over Newcastle United, Crystal Palace and Stoke City have lifted the Wearsiders out of the relegation zone, and optimism is flooding back to the Stadium of Light.
Sunderland are now looking like a very well drilled side, and they will be keen to highlight their improvements this weekend, when they face Arsenal at the Emirates Stadium.