Los Colchoneros secured a draw away to Chelsea on Tuesday (5 December) but while it was enough to deny the Blues top spot on Group C, results elsewhere consigned them to a third place finish and Europa League football next season.
Griezmann's future remains under intense speculation, heightened by the recent release of his book where he openly describes a move to United as a "possibility" after a move to Old Trafford fell through during the summer transfer window.
But Simeone is confident his side's elimination from Europe's premier competition will not hasten the exit of his star players.
"On the contrary, it is a new challenge," Simeone insisted in his post-match press conference. "Everything that is bad, we make into a positive."
Griezmann was heavily linked with a move to Old Trafford towards the end of the 2016-17 season, openly declaring in May he felt his chances of moving to Old Trafford were "six out of 10". Those odds were seemingly enhanced after United's Europa League success guaranteed them a return to the Champions League, with the player then reportedly informing Atletico of his decision to leave.
United instead chose to switch their focus on signing a natural number nine after losing Zlatan Ibrahimovic to a long-term injury. The situation was also complicated when Atletico were hit with a transfer ban prohibiting them from registering new players until January 2018. Griezmann went on to sign a new contract with the Madrid giants, putting the matter to bed for at least another year.
United remain linked with the former Real Sociedad star who has made little secret of his interest in a move to Manchester, opening the door for the move in his new book Behind the Smile. Any club wishing to sign him however will have to dig deep. Griezmann signed a new deal with Atletico in June which temporarily raised his release clause to €200m (£182.1m). But as of 31 August – the day the transfer window closed in England – it was reduced to £91.5m – the fee United were ready to pay earlier that summer.