NEIL Harris has warned this transfer window will be the "hardest so far" as the club gears up to building a squad for a second successive Championship campaign.
After an impressive season, Millwall will hope to keep hold of their key players and address positions for strengthening.
They are likely to be centre-back and left-back, as well as a wide player and centre-forward, at least. Harris again wants to work with a relatively small first-team squad.
The club will also announce their retained list, with several players finding out if they are to be offered new deals.
"There will be no announcement in the next few days, we will take our time and make our decisions known at the right time," Harris said.
"We are thinking about how we're going to build on an excellent season.
"Some players who haven't featured a lot might want to get out and play regularly on a Saturday afternoon. As ever we're respectful of that.
"It's going to be difficult recruitment-wise for us, it will be the hardest window so far. We work best with a small, settled squad.
"It was good to add more competition in the second half of this season, but it will be around 21 first-team players again. That's the ideal number with youngsters backing it up.
"There will also be younger players going out on loan again."
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