Sterling was left out of the matchday squad for the weekend win over Fulham, whilst Ake is yet to be involved since he returned to training following a muscular injury which has kept him out since December.
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However, the defender is close to a comeback and Pep Guardiola says he will use his summer signing as soon as he is cleared to return.
“I want Nathan to be involved as soon as possible,” he said at his pre-match press conference.
“He flies with us and as soon as he can be involved, I want to do it.
“He [Sterling] travels with the team for tomorrow, of course. All the squad travel to Budapest.”
Sterling was a surprise omission at Craven Cottage, though Guardiola explained afterwards that rotating his team is a must if City are to challenge for honours on four fronts.
The 50-year-old acknowledged that all players are unhappy when they are left out, but says Sterling, like the rest of his squad, are respectful of his decisions and responded in the right way.
“I don't expect the guys who are not selected are happy,” he added. “It is normal.
“It has happened since football was created. Raheem in this case has been so important and is so important.
“All the players respect my decisions. I never found in my career one player who was happy when they don't play, but they react and behave really well.
“Sometimes during the season, for example when we travelled to Stamford Bridge, we had 14 first team players and then it is easy to make the selection and everybody is happy.
“When you have 20 top class players who have had incredible success, it will always be unfair on them. That is the point.
“I now have 20 players, I trust them, I love them, they are the main reason why we are in the position where we are in the Premier League and Champions League and Carabao Cup and FA Cup.”
City will be the home team in Budapest, which has hosted both legs in our last 16 tie after COVID-19 restrictions prevented the games taking place in England and Germany.
Bernardo Silva and Gabriel Jesus got the goals in a dominant first leg display, but Guardiola says his team will be aiming for another victory, rather than attempting to protect our 2-0 lead.
“We have to play the game like we did against Fulham and Southampton, not like against United,” said Pep.
“Play and win the game. Focus on winning the game - this is our target.
“I know the quality they have. It starts with Sommer and finishes with Thuram. Like all teams they have had bad moments.
“It is a final. They have nothing to lose. I am sure they will try to overcome the situation.
“I have incredible respect for Gladbach and Marco [Rose]. They have weapons and they know how to use it. I want to see the team try to win the game.”
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