Atalanta ended any lingering fears about relegation after continuing their recent good form with a 2-0 home victory over Fiorentina, who still have a little work to do before they can celebrate safety themselves.
Goals at the start of either half from German Denis and Giacomo Bonaventura earned Atalanta a third win in four games and moved them 11 points clear of third-bottom Lecce with only three games remaining.
Considering they started the campaign with a six-point penalty for match-fixing, the Bergamaschi will be delighted to have secured their top-flight status with room to spare - especially as their final three fixtures see them facing AC Milan, Lazio and Juventus.
For Fiorentina, the defeat, which saw Stevan Jovetic miss a second-half penalty, brings to an end an impressive run which had seen them pick up eight points from four games, including away victories over Milan and Roma.
Atalanta took the lead with the first real chance of the match in the 11th minute when Denis found the top corner of the net with a header from Gianpaolo Bellini's cross.
That proved to be the home side's only serious effort in the first half but it was still enough to see them leading at the break as Fiorentina failed to make the most of several opportunities to draw level.
Jovetic had three shooting chances but failed to hit the target with any of them, while Valon Behrami's radar was well off with two other efforts. Houssine Kharja also failed to trouble home goalkeeper Andrea Consigli with his 34th-minute shot.
Fiorentina were made to pay for leaving their shooting boots at home as Atalanta doubled their lead six minutes into the second half.
Visiting goalkeeper Norberto Neto had just moments before produced a good save to deny Denis but he was left with no chance as Bonaventura made it 2-0 with a superb shot from the centre of the area.
Neto was then called on again to save well from a Cristian Raimondi header, before Fiorentina earned themselves a great chance to get back into the game when Raimondi brought down Maxwell Boadu Acosty inside the area in the 67th minute.
However, Jovetic could not take advantage as home goalkeeper Andrea Consigli saved his resulting penalty, and after that Atalanta held on relatively comfortably to take the points.