Ben Olsen's side entered Sunday knowing that a win would complete their late-season surge to the postseason, and they got just that with a 3-1 victory over NYCFC.
Wayne Rooney scored in the eighth minute to put his side ahead, finishing a Luciano Acosta assist following a winding run from the Argentinian playmaker.
Just 16 minutes later, Acosta scored a goal of his own, curling in a shot past Sean Johnson to give the home side a 2-0 lead it would never relinquish.
Rooney added another in the second half, scoring from the penalty spot to emphatically lock up a playoff berth despite a consolation finish from David Villa.
In the West, Ibrahimovic and the Galaxy stayed in the race thanks to a win over Minnesota United.
The Swedish star scored one and assisted another in the 3-1 victory and the Galaxy will need all three points next time out against the Houston Dynamo to stay in the hunt.
As things stand, Sporting KC sits top with 59 points with FC Dallas and Los Angeles FC also in the hunt following the expansion side's draw with the Vancouver Whitecaps that eliminated the Canadian team from playoff contention.
Gerardo "Tata" Martino's side were led by an early Franco Escobar finish and a Johan Kappelhoff own goal.
With the victory, Atlanta can lock up the Supporters' Shield next weekend with a win over Toronto FC in their season finale.
Alejandro “Kaku” Romero Gamarra was the lone scorer on the day, keeping the Red Bulls in the hunt for the league's top regular season prize.
Two teams are still alive for the one remaining playoff spot in the East, with the Columbus Crew two points clear of the Montreal Impact heading into the final week of the season.
While the Crew fell to a 2-1 loss against lowly Orlando City in a match that would have secured a postseason spot, the Impact managed to close the gap with a 2-0 win over Toronto FC.
Columbus can lock up a playoff spot with a win over Minnesota United next week, but anything short of that will make things very interesting, with the Impact taking on the New England Revolution in their finale.
In other action, Chris Wondolowski's pursuit of the league's goal record remained on hold as the San Jose Earthquakes settled for a 0-0 draw with the Colorado Rapids that clinched last place for the California team, while the Seattle Sounders picked up a 3-2 win over the Houston Dynamo to continue their own run after recently sealing a postseason spot.