Alex Oxlade-Chamberlain will miss the "vast majority" of the forthcoming season as the Liverpool and England midfielder focuses on rehabilitation from a serious knee injury.
The 24-year-old sustained multiple ligament damage during the first leg of the Reds' Champions League semi-final triumph over Roma in April.
Oxlade-Chamberlain was set to play a key role in the final weeks of Liverpool's campaign, which concluded with defeat in the final of the same competition, and England's trip to the 2018 World Cup.
Surgery eight days after the Roma match was a success and manager Jurgen Klopp explained it was a matter of waiting until the time was right before disclosing the severity of the midfielder's condition.
"It feels like now is an appropriate time to tell people that for Ox this coming season will be about focusing on recovery and rehab," he told the club's official website.
"We have known this from pretty much the day after he got the injury and after the successful surgery, we were sure of it. I hope everyone treats this information responsibly.
"There has been no change, no setback – it's exactly on the schedule we expected and planned for. The new information is that we're now giving more detail publicly."
Oxlade-Chamberlain joined Liverpool from Arsenal on transfer deadline day last August for a reported £35million fee and hit a rich vein of form after the turn of the year.
He scored five times in all competitions, including a superb long-range strike in the Champions League quarter-final win over Manchester City.
"It is typical of Ox that he didn't want the news to overshadow the end of the season and, to be quite honest, we thought we could wait and tell people at an appropriate time," Klopp added.
"His surgery – which he had on the day of our second leg in Roma – has been completely successful and his recovery has started superbly well.
"But the truth of the matter is that we are preparing this season knowing he will not be with us on the pitch for competitive matches for the majority of it. If we do see him back this season it will be a bonus."
Liverpool have already bolstered their midfield during the close season, with Naby Keita completing his pre-arranged switch from RB Leipzig and Fabinho arriving from Monaco.
Switzerland international Xherdan Shaqiri, who joined from Stoke City last week, provides an additional wide attacking option – another of the roles Oxlade-Chamberlain previously filled.
Klopp's men open their Premier League campaign against West Ham on August 12.
|Butler opens up about heated Timberwolves practice|
|Spurs achieved ´mission impossible´, says Pochettino|
|Dembele stunner pleases Barca boss Valverde|
|Van Dijk lauds ´fantastic´ Alisson|
|Van Dijk´s tackle on Mertens worthy of red card – Ancelotti|
|Klopp ´would have paid double´ for Alisson|
|Klopp: I don´t care about Madrid revenge mission|
|Tension and anxiety got to Inter, laments Spalletti|
|Tuchel hails magnificent PSG as Red Star win seals last-16 spot|
|Mbappe admits frank discussions inspired PSG´s Champions League progress|
|Klopp: Napoli had no answers to outstanding Liverpool|
|Pochettino proud of ´massive, massive achievement´ for Spurs|
|Barcelona equal Champions League record|
|Composed and controlled Liverpool see off Napoli to progress|
|Tenerife back to winning ways, AEK beat Hapoel|
|Howedes ´hurt´ after emotional Schalke return ends in defeat|
|Kane ´buzzing´ over ´not bad´ draw at Barcelona|
|Robertson hails Alisson´s ´unbelievable´ save as Liverpool progress|
|Red Star Belgrade 1 Paris Saint-Germain 4: Neymar brilliance helps secure Group C top spot|
|Inter 1 PSV 1: Icardi header not enough for the Nerazzurri|
|Liverpool 1 Napoli 0: Superb Salah sends Reds through|
|Club Brugge 0 Atletico Madrid 0: Simeone´s men miss out on top spot|
|Barcelona 1 Tottenham 1: Lucas rescues Spurs late on to secure progress|
|Monaco 0 Borussia Dortmund 2: Guerreiro double snatches top spot from Atletico|
|Butler´s groin strain ´nothing significant´ – 76ers coach Brown|
|Woakes, Curran among leading lights at IPL auction|
|Blue Jays release five-time All-Star Tulowitzki|
|Mourinho: Professionals care more than the fans|
|Casillas reaches 100 Champions League wins|
|Expansion franchise Cincinnati sign Garza, send Kamara to Rapids|
|Manchester City sign United States goalkeeper Steffen for reported £7m|
|Schalke 1 Lokomotiv Moscow 0: Russians miss chance for Europa League reprieve|
|Galatasaray 2 Porto 3: Terim´s men into Europa League after penalty drama|
|Jackman leaves Dragons role|
|Tottenham boosted as Barcelona bench Messi|
|Mane and Henderson in Liverpool XI to face Napoli|
|Mourinho shoots down question over how to get the best from Pogba|
|Ronaldo to start as Allegri aims to avoid Champions League big guns|
|Odriozola: I´m in love with Benzema, he´s the best number nine in the world|
|Vikings fire OC DeFilippo after loss to Seahawks|
|Marcelino suggests Valencia open to Batshuayi departure|
|Bottas to make rally debut in title-winning M-Sport Ford Fiesta|
|Kovac dismisses Pavard speculation|
|Yaya Toure leaves Olympiacos after just five appearances|
|Riise challenges Liverpool to banish Champions League disappointment against Napoli|
|We rallied around it - Durant on Green confrontation aftermath|
|Valencia ´p****d off´ with Fellaini´s controversial Young Boys winner - Soler|
|More must be done to combat racism at Premier League grounds – Chalobah|
|Napoli will not sack ´big signing´ Ancelotti if they miss Champions League qualification, says De La|
|Guardiola not interested in ´exceptional´ Saul|
|Shai gives Windies hope with thrilling ODI run chase|
|Ten Hag unsure whether to risk Ajax stars against Bayern|
|Erasmus to work with Bulls as Springboks assist Super Rugby sides|
|Paul Gascoigne pleads not guilty to sexual assault|
|Joshua is ´begging´ for unification fight, claims Wilder|
|Silva, Fernandinho add to Guardiola´s injury woes|
|Hosszu storms to 14th gold, Seto smashes Le Clos´ world record|
|Raheem is an incredible human being - Guardiola rallies behind City star Sterling|
|Sexton pens IRFU extension until 2021|
|Ajax boss Ten Hag can do big things, says Bayern chief Rummenigge|
|He´s good at basketball – Kerr running out of superlatives for Curry|
|Green thrilled to make Warriors return in victory over Timberwolves|
|Madrid squad great and humble - Solari responds to Ronaldo|
|Langer unsure what to expect from Perth wicket|
|Fournette subjected to alleged racial abuse in Titans loss - Marrone|
|Better and better - Mbappe hails Neymar link|
|It´s the end of one of the best movies you could ever see - James pays tribute to retiring Wade|
|NASA invites Curry to see moon rocks|
|No plan B for LaLiga Miami game after Barcelona withdrawal|
|Messi´s English haul, Neymar eyes hat-trick record - Champions League in Opta numbers|