The retired England international started the top of the table clash in the middle of the park alongside his compatriot Jordan Henderson and Dutch star Georginio Wijnaldum.
However, the 32-year-old was substituted in 29th minute in what was a blow to Liverpool FC’s hopes of beating the Citizens to lay down a huge marker in the title race.
Milner has been one of the Premier League’s standout performers in the opening months of the Premier League season to help Liverpool FC challenge Chelsea FC and Manchester City.
The two-time Premier League winner has scored two goals and has made two assists in 11 appearances in all competitions in the current campaign.
Milner’s relentless work rate has earned the former Leeds and Newcastle midfielder praise this term, regularly being hailed as the unsung hero in Klopp’s team.
Speaking at his post-match media conference following Liverpool FC’s goalless draw with Manchester City at Anfield on Sunday, Klopp provided an early update on Milner’s injury.
“How much [is Milner’s injury serious]? It’s too early, I don’t know,” Klopp said. “I asked him ‘big one?’ and he said ‘I don’t think so, but big enough that I go off.’”
Milner has showcased his unrivalled versatility since his move to Liverpool FC from Manchester City in a free transfer during Brendan Rodgers’ stint in charge of the Anfield outfit.
The former Aston Villa man completed a switch in 2015 and Milner has gone on to score 17 times in 143 games in all competitions over the past three seasons or so.
Klopp used Milner in an unorthodox left-back role in the Liverpool FC team throughout the 2016-17 season after the German head coach opted to start with the Englishman ahead of Alberto Moreno.
Milner will be hoping to add a third Premier League crown to his collection after his previous successes with Manchester City in 2012 and 2014.
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