Samaras has been a key part of the Hoops' European journey this season but will have a scan on Thursday to see if he is able to feature in the first leg at home to the Italians on February 12.
Celtic boss Lennon is more confident that defender Emilio Izaguirre, who also went off before the break with a knee injury, will recover quickly.
Lennon said: "Emilio should be okay. He just felt a little bit of tightness at the back of the knee.
"Georgios, we think, may have a slight strain but he will be scanned and we are hoping it is not too serious.
"It is two weeks until Juventus and if it is more than a mild strain then it will be a concern.
"At the minute it doesn't look too bad but the scan will reveal more."