Aguero left the field during extra time of Sunday’s game at Wembley and appeared to be a doubt for Thursday’s crucial derby at the Etihad Stadium.
But his condition has swiftly improved and manager Pep Guardiola says the Argentine will be available for selection against Jose Mourinho’s side after joining in with training on Wednesday morning.
Gabriel Jesus is also ready to return after three months on the sidelines with a fractured metatarsal but David Silva, who went off after 23 minutes of the game with Arsenal after a heavy challenge from Gabriel, remains a serious doubt.
“David Silva real, real doubt - I don’t know if he will be ready to play after what happened in the first minutes in the semi-final,” Guardiola said.
“Gabriel has no pain at all so is ready but [after] three months out his physical condition is not optimal.
“Sergio is much better. Today he make a part of the training session. Tomorrow he will be ready.”
United arrive just one point behind City in the race for a top-four position – and they have injury problems of their own, with Zlatan Ibrahimovic likely to be out until the new year.
The Swede, who has scored 28 goals in all competitions this season, had been Mourinho’s first-choice striker until he ruptured his anterior cruciate knee ligaments in the recent Europa League game against Anderlecht.
It’s been an impressive debut campaign in English football for the former Barcelona and Inter Milan man - but Guardiola played down the significance of his absence, saying it opens up a spot for one of United’s other talented forwards to fill.
“Of course they have been playing the last games without him but they achieve to play the way Jose Mourinho wants they win a lot of duels between the players,” Guardiola said.
“Ibra is a great player but they also have lots of good players like Lingard, Young and Rashford and they find spaces between the lines.”
