Manchester City are assessing where it went wrong after another premature Champions League exit.
Here, the PA news agency looks at some changes they may need to make to succeed in the competition.
Strengthen the defence
City's error-prone back line not only undermined their Champions League campaign but it was their Achilles heel all season. City may have had good reason not to pay the fee demanded by Leicester for Harry Maguire last year but not seeking an alternative after the departure of Vincent Kompany was a mistake. Moves have now been made to strengthen in this area with the signing of Nathan Ake and there could be more to come with the club linked with Napoli's Kalidou Koulibaly. Greater depth is also needed in the full-back positions.
Regenerate
The team will also need to be refreshed in other areas. With David Silva leaving the club this summer, now only Sergio Aguero remains of the great mainstays of the past decade. Aguero, City's record goalscorer, is also approaching the end of his career. Gabriel Jesus is his natural successor but he has a long way to go to prove he can consistently match Aguero's brilliance. Regardless of that, with little back-up, other attacking options may be required. Kevin De Bruyne and Raheem Sterling are already senior players but others such as Aymeric Laporte, Riyad Mahrez and Bernardo Silva also now need to step up in responsibility, while Phil Foden needs to become a regular starter.
Cut the tinkering
City manager Pep Guardiola has been brilliant for the club and English football, playing some scintillating football that has brought him six major trophies, including two Premier League titles, in the past two years. For some reason Europe, despite his past success in winning the Champions League with Barcelona, has been his undoing. In the past four years, Guardiola has repeatedly been accused of "over-thinking" matters and this has certainly been the case since Saturday's latest exit at the hands of Lyon when he deployed an unfamiliar system with disastrous results. After lockdown City have enjoyed some emphatic wins (4-0 v Liverpool and Watford, 5-0 v Newcastle, Burnley, Brighton and Norwich) as well as their memorable triumph over Real Madrid. Simply sticking to what seems to work well more could be advantageous.
Change the psychology
In the short term, City will obviously need to pick themselves up before the start of the next campaign. After ending the season on such a low note with Saturday's anticlimactic quarter-final loss in Lisbon, this will be a difficult task. The new season starts in September and there is little time to rest and prepare. Beyond that, there are also the psychological scars of another European disappointment. Next season will be City's 10th in succession in the Champions League and they have only reached the semi-finals once. They can no longer use inexperience as an excuse. They need to make sure they do not get weighed down by the increasing burden of expectation.