Neil Harris will be aiming to build on an impressive first season back in the Championship by improving the squad.

Millwall barely made any changes to the starting XI in the last two transfer windows which makes their success this season even more impressive. However, they will need to bring in new personnel to give them added depth, at the very least, if they want to replicate this season and keep challenging for the play-offs in the future because other clubs will certainly spend significant funds.

The squad is mainly made up of League One players, so they will need to get rid of some of the players on the periphery who aren't up to the standard required in the Championship.

Here are three players that could leave in the summer...

Martin was brought in as a free agent last summer to act as back-up for Jordan Archer. This means he has been limited to one league appearance this season.

The Lions have Harry Girling coming through the ranks, so he can act as back-up next season as well as playing in the cup competitions. Therefore, they won't need Martin, so he could be released as a free agent again. It was always likely to be a short-term solution with little financial costs as Millwall navigated through their first season back in the Championship.

Webster started the season in the first-team alongside Hutchinson in the centre of defence, but suffered a cruciate ligament injury early in the season. Jake Cooper has come in to replace him and hasn't looked back since as he has fitted in perfectly at this level.

Cooper is unlikely to lose his place because he played a key part in the defence that enabled Millwall to go on a 17-game unbeaten run. This might convince Webster to move elsewhere in order to get a first-team place.

Harris is likely to bring in more centre-backs in the summer as well because Jason Shackell is only on loan, so they have three senior players for that role. Therefore, the competition is likely to increase for them roles which makes it harder for Webster to get back in the first-team.

Ferguson has been mainly used as a substitute this season, but has had little effect because he is yet to score or provide an assist in the league. The Lions need better options to change games from the bench and Ferguson just doesn't provide that with youngster Fred Onyedinma having much more of an impact.

He was only signed in 2016, but Millwall have made a lot of progress since then so they need to adjust to that accordingly in terms of personnel with Ferguson being one of the players to lose out because of that, but otherwise they risk stagnating.