No one knows if this season could be the end of Pep Guardiola at Manchester City, but if he doesn't improve the performance of Manchester City this season, I am 90% certain he will take a break from football. I even thought Liverpool and Arsenal would end in a draw since they played upto 82nd minutes without scoring a goal, but Szoboszlai lucky free kick separated Liverpool and Arsenal, and it was enough to earn Liverpool the three points.
I do not think Manchester City will sack Guardiola. Guardiola is the best coach in Manchester City's history. He transformed City from a mediocre club into the best club in europe. The team consistently showed great dominance in the Premier League. City also won the Champions League and FA Cup with the help of Guardiola.
Anyway, it is possible that if Guardiola fails this season, he will voluntarily leave Manchester City. Guardiola is only 54 years old. He will not think of retiring so soon. He will probably want to take on a challenge with a new team.
Guardiola's contract with City ends in 2027. So even if he fails, he may decide to stay at the Etihad until 2027. Whatever, I am pretty sure that Manchester City will not be the Premier League champion this season.