Manager Martin O'Neill's hard-line approach to management is the secret behind Sunderland's transformation, says midfielder Sebastian Larsson.
O'Neill took over in December with the club 16th in the Premier League table, but four wins in six games have lifted the Black Cats to 10th.
"He made it very clear it is time to start picking up some points," Larsson, 26, told Football Focus.
"And a big responsibility is on us, the players, to do that."
O'Neill's impact was immediate as the Black Cats came from behind to beat Blackburn at the Stadium of Light in the Northern Irishman's first game in charge.
That afternoon, Larsson scored the winner with a brilliant, trademark free-kick.
"It was the perfect start for the new manager," added Larsson. "The crowd was buzzing and we desperately needed the three points.
"It was a big relief for the players and the fans."
Larsson joined Arsenal at the age of 16 but made only a handful of appearances in three seasons with the Gunners before joining Birmingham City.
Last summer, the Swede swapped the West Midlands for Wearside on a free transfer.
Larsson has always been well known for his delivery from set-pieces but this season he has also become the club's top scorer with six goals.
Sunderland have made a habit of scoring late in games, which Larsson believes is another example of O'Neill's uncompromising approach.
"He demands you give 100% for the cause throughout the game," he said.
"That has paid off for us in the latter stages of games with some late winners which has been terrific."
Sunderland, who face a trip to Chelsea on Saturday, beat Championship side Peterborough 2-0 in the FA Cup third round last weekend.
Victory set up a fourth-round meeting with Middlesbrough and Larsson said O'Neill is targeting significant progress in the competition.
"He made it clear to us how important the Cup was," continued Larsson. "He wanted to make sure we beat Peterborough and progressed to the fourth round.
"It will be an interesting game, a local derby against Middlesbrough. I have never been involved in one but I am looking forward to it."