The Portugal international missed all five matches in November with a calf problem but returned at the start of December and has been an ever-present this month.
Guardiola's side have lost eight of their past 11 games in all competitions following the devastating 2-1 defeat in the Manchester derby at the Etihad Stadium on Sunday.
Manchester City have won just once in 11 games in all competitions, a run that includes eight defeats.
Enzo Maresca's high-flying Chelsea beat Brentford 2-1 at Stamford Bridge to close to within two points of long-time leaders Liverpool, who have 36 points.
Josko Gvardiol's first-half goal appeared to have won the game for the Premier League champions but Bruno Fernandes levelled from the penalty spot in the 88th minute and the impressive Amad Diallo poked home the winner two minutes later.
Guardiola's side have won once in their last 10 matches in all competitions, sit fourth in the Premier League, eight points behind leaders Liverpool, and are in danger of a humiliating exit from the Champions League.
However, profits dipped from £80.4 million in City's treble-winning 2022-23 campaign to £73.8 million last season.
Manchester City were plunged further into crisis on Wednesday after falling to a 2-0 defeat at Juventus which threatens their chances of reaching the last 16.
The English champions stand accused of 80 breaches of financial rules between 2009 and 2018, plus a further 35 of failing to cooperate with a Premier League investigation.
Foden has scored 17 goals and grabbed eight assists in 34 league games this season playing centrally as well as on the wing when needed. He has 25 goals and 11 assists in all competitions.
"That's our mindset now, win that last game, give the fans a good last game and we'll see. It's out of our control, we just focus on our game."
Former Manchester United and Manchester City striker Carlos Tevez on Friday quit as coach of Argentinian club Independiente.
Erling Haaland has urged his Manchester City teammates to "relax" after they closed in on making English football history with a 2-0 win away to Tottenham Hotspur.
Manchester City goalkeeper Ederson will miss Sunday's concluding game of the Premier League season and next week's FA Cup final, the club announced Thursday.
"The tennis players say 'the serve to win Wimbledon', the last match, is the most difficult," Guardiola told the BBC.
City almost conceded an equaliser to Son Heung-min late on.
Manchester City have lost all four Premier League matches they have played at the Tottenham Hotspur stadium but the defending champions must change that when they visit the North London side on Tuesday, manager Pep Guardiola said.
Ange Postecoglou said Tottenham will go all out to beat Manchester City on Tuesday, even though it could open the door to bitter north London rivals Arsenal to win the Premier League.
Manchester City have lost all four Premier League matches they have played at the Tottenham Hotspur stadium but the defending champions must change that when they visit the North London side on Tuesday, manager Pep Guardiola said.
