Atalanta head coach Gian Piero Gasperini said Josip Ilicic is unlikely to be fit to face Paris Saint-Germain in the Champions League quarter-finals.
Ilicic has starred for high-flying Atalanta this season, scoring 15 Serie A goals and five during the club's memorable run to the Champions League's last eight.
However, Ilicic is a doubt for the August 12 showdown against Ligue 1 holders PSG in Lisbon, having not featured since Atalanta's 2-2 draw with Serie A champions Juventus on July 11.
Speaking after Tuesday's 2-1 win over Parma, Gasperini told Sky Sport Italia: "It's a pity that in the decisive moments of the season, we have to do without key players.
"We had months without Duvan Zapata, now Ilicic is out and the more time passes, the less likely we are to get him back playing for the Champions League. It's going to be really difficult to have him ready.
"The team is doing well to adapt and try to find a different balance, because we have players with very different characteristics, for example Mario Pasalic, Gomez and Malinovskyi.
"Without Duvan Zapata, we had to make changes and find a different way, so we try to make up for these issues with other qualities."
"Ilicic is fundamental for us, it was his season up until March, he was devastating in both Serie A and Europe," he continued.
"It would be like Juventus missing Paulo Dybala or Lazio playing without Ciro Immobile, even Inter without Romelu Lukaku."