Liverpool centre-backs Virgil Van Dijk and Joe Gomez both "look really good" as they build towards comebacks from long-term injuries, manager Jurgen Klopp has said.
The Reds boss has also delivered positive updates on two other defenders in Trent Alexander-Arnold, who was injured in the lead-up to Euro 2020, and Joel Matip.
The four players are working on their fitness at Liverpool's pre-season training camp in Austria.
Defensive problems were among the chief reasons why Liverpool were unable to mount a strong Premier League title defence last term.
The loss of Van Dijk was felt particularly strongly, with the Dutchman playing no part in the campaign after suffering a knee injury in the Merseyside derby at Everton in October last year.
Gomez was also ruled out for the season with a knee problem a few weeks later.
Klopp told the club's website: "Virg and Joe will not have double sessions now for the first few days with the team. They have a second session of the day but it's with the rehab department, physiotherapy – these kinds of things.
"That's for these two. (They) look really good. I don't know exactly when we can make the next steps but it will happen in the next four weeks. For sure, we will get a big step forward."
Matip, also a centre-back, did not feature again suffering ankle ligament damage in February.
Right-back Alexander-Arnold hit form late in the season to earn a place in England's summer plans but then sustained a thigh injury in a friendly against Austria last month.
Klopp said: "Joel looks good, absolutely, he is the closest probably to normal training and then we will see when we get him started for playing.
"Trent was a serious enough injury but now not a major one, I would say.
"He is close but for the moment, probably the next five or six days he has a special programme – from time to time with the team, from time to time by himself. But then in five or six or seven days he should be in normal team training."