Alisson is making "steady progress" in his recovery from a calf injury, but there is still no timescale on his return to action, according to Liverpool goalkeeping coach John Achterberg.
The Brazilian goalkeeper has been out of action since the opening day of the new Premier League season, when he had to be substituted in the first half of Liverpool's 4-1 win over Norwich City on August 9.
Initial reports indicated an absence of between four and eight weeks for the 26-year-old, who played every minute of Liverpool's remarkable 2018-19 Premier League campaign:
Over a month on from the initial injury, Achterberg provided an update on his progress, but he preached caution on Alisson returning too quickly, per James Carroll on Liverpool's official website:
"Ali has been working with Dave [Rydings] in the gym a lot to improve the strength and try to keep the fitness levels up. In the last few days, he has been out on the pitch to do some catching and footwork, as well as small passing drills.
"He has made steady progress, but it is difficult to say how long it will take or how it will progress. It needs time, and we cannot look too far ahead, so we take each day as it comes, see how he feels and then make progress from that."
Alisson played a key role last term in turning Liverpool from also-rans into the best Premier League runners-up in history:
His arrival at Anfield from Roma in July 2018, paired with Virgil van Dijk's move to Liverpool from Southampton six months earlier, was vital to the Reds' defensive solidity last term.
In the eight seasons preceding 2018-19, Liverpool were weak in defence, conceding an average of over 44 goals per campaign, which undermined a largely consistent attacking unit.
With Alisson and Van Dijk in the squad, Jurgen Klopp's side conceded just 22 goals in the Premier League last term, the best defensive record in the division.
As a result, they were able to go blow for blow with Manchester City before finishing second by the slimmest of margins:
If they are to continue that kind of form in 2019-20 and have a chance of breaking their 30-year title drought, Liverpool need Alisson back in the side.
Summer signing Adrian has proved a worthy deputy in the Brazilian's absence, but Klopp will be desperate to see his No. 1 return as soon as possible with the Premier League resuming this weekend after the international break.