Jürgen Klopp confirmed on Friday that his No.20 is facing "a couple of months" on the sidelines having sustained a thigh injury during the Reds' Audi Cup final defeat to Atletico Madrid.
Lallana has since taken to Instagram to express deep disappointment over his lay-off - though he remains confident that the team will start the season well without him.
He wrote: "As gutted as I am personally to be missing the start of the season, I have nothing but confidence in how the team is going to do.
"[The] lads are in great shape and ready to attack it. My focus is getting back and supporting the boys. Thanks for all the kind messages #ynwa."