The France international was speaking a day after Lyon were held to a goalless stalemate by Ajax Amsterdam that leaves the Dutch side needing just a draw from their final Group D match to reach the last 16 along with runaway leaders Real Madrid.
Lyon (5) are three points behind Ajax (8) and have a vastly inferior goal difference, so even a big win at Dinamo Zagreb in the final round of matches may not be sufficient enough to claim second place in the group.
"We have one foot in the Europa League," France keeper Lloris told reporters of the side's probable fate resulting from a third-place finish in the group.
Lyon dominated in the closing stages against Ajax and came close to breaking the deadlock through Michel Bastos and Yoann Gourcuff, but they now face the prospect of not making it to the last 16 for the first time since the 2002/03 season.
"It's a disappointment. When you have ambition, you have to do better than that," said Lloris, who also pulled off a couple of superb saves.
"We should have played with more ambition and be a little bit meaner to go and get a good result."
Lyon had the talismanic Lisandro Lopez starting for the first time in 12 weeks after an injury layoff, but the Argentine striker lacked sharpness and created only once chance early on before being replaced midway through the second half.
Although only a minor miracle would enable Lyon to advance, Lloris said the Dinamo Zagreb game would still be important.
"We have to win this game for our public image," he said.
"Miracles are possible but it will be difficult."
