Liverpool coach Jurgen Klopp has revealed that Egyptian winger Mohamed Salah and German midfielder Emre Can had been feeling unwell before Manchester City's clash, which is why he pulled them off during the game.
The Reds claimed a dramatic 4-3 win over Manchester City which ended the Premier League leaders' unbeaten start to the season.
"Before the game, Emre and Mo [were] on the way to becoming ill and obviously with Emre it was a little bit more difficult," he told reporters after the game.
"[At] half-time [it] was already difficult but we have not a lot of options so he tried everything.
"Usually, 4-1 is a good moment [to make a substitution] but against City maybe it's difficult!"
Can was replaced in the 79th minute while Liverpool were leading 4-1, then Salah in the 88th minute as Manchester City managed to close the gap to 4-3.
Salah, who joined Liverpool last summer, maintained his excellent displays at Anfield as he provided an assist for Sadio Mane to score the third before turning into a scorer to make 4-1 and increase his tally to 18 Premier League goals.
(For more sports news and updates, follow Ahram Online Sports on Twitter at @AO_Sports and on Facebook at AhramOnlineSports.)