Ngumoha, who had been Liverpool's standout performer on the day and provided the assist for Ryan Gravenberch's opening goal, was withdrawn in the 67th minute and replaced by Alexander Isak. The decision sparked a loud chorus of boos from sections of the Anfield crowd, with frustration already building over another disappointing result.
Slot, however, was quick to clarify that the teenager had signalled he could not continue after experiencing cramp.
"There were a lot that didn't agree with the change, which is completely understandable," Slot explained. "He had cramps before then when he went to the floor. I had contact with him and he said that it was enough, so that's why I took him off."
He added that Ngumoha was not in a condition to maintain his intensity. "He is not at the level yet where he can play at 50 or 60 percent and make a difference. He wasn't fit enough to sprint and make his actions. If you don't know that, then you feel like ‘why is he taking him off?' But that wasn't my intention."
Liverpool had started brightly and could have gone 2-0 up before Chelsea grew into the match, with the visitors later equalising from a set piece—an ongoing problem for Slot's side this season.
The draw extended a pattern of inconsistency, with Liverpool once again struggling to control a game they had initially dominated. The result also meant missed opportunities in the race for European qualification, adding to the tension inside the stadium.
"There was a completely different intensity in the second half," Slot said. "We went close a few times, hit the post and the bar again like so many times this season, but we were not able to control their players."
Liverpool's defensive fragility from set pieces remains a concern, with the team now having conceded 18 goals in such situations this campaign—second only to Bournemouth in the league.
The frustration inside Anfield did not end with the substitution. More boos followed the final whistle, reflecting growing dissatisfaction with a season that has fallen below expectations.
Slot acknowledged the reaction, linking it to both the performance and broader frustrations. "That's probably got something to do with us not winning," he said. "It completely makes sense. People are disappointed if Liverpool don't win. Especially in a season where we haven't won as much as people expect."
Midfielder Ryan Gravenberch, who scored Liverpool's goal, defended the team. "OK, we didn't win, but I don't really think we deserved this," he said. "We need the fans."
Despite the current mood, Slot remains convinced he can rebuild trust at Anfield.
"Yes I do," he said when asked if he could win the supporters back. "Not this season, the fans will have their opinion and it will not change. But if we can have the (English) summer that we are planning then I am 100 percent convinced we will be a different team next season."
He added that internal clarity over Liverpool's shortcomings will shape their rebuilding process. "It is really clear what we are lacking this season and we are trying to fix it."
For now, though, the focus remains on stabilising a campaign defined by inconsistency, frustration, and growing pressure at one of English football's most demanding stages.
