Marc Wilmots is keen to plan for a Belgium defence without injury-plagued captain Vincent Kompany.
Kompany made just 22 appearances for Manchester City in all competitions in 2015-16 and a thigh problem has ruled him out of Euro 2016.
Belgium suffered further blows in their preparations for the tournament in France with defenders Nicolas Lombaerts, Dedryck Boyata and Bjorn Engels all pulling out of the squad due to injuries.
After shoddy defending enabled Finland to take the lead through Kasper Hamalainen in a 1-1 draw in Brussels on Wednesday, Wilmots admitted a new consistent pairing at the back is needed to replace Kompany and former international Daniel Van Buyten.
"We need time to establish this defence. An understanding will come, especially with the high pressing we tried," he told RTBF.
"We had Kompany and Van Buyten before, we must now build a new central defensive pairing for the future of the [Red] Devils."
Substitute Romelu Lukaku earned Belgium the draw when he chested home in the 89th minute.
With his team only converting once from a total of 35 shots and Finland goalkeeper Lukas Hradecky making seven saves, Wilmots admitted it was a frustrating night.
"You can see things in different ways. Our four defenders played high and created chances, but face it, there were five Finnish defenders and it was difficult to find an opening. They also had a sensational goalkeeper," said the Belgium coach.
"This kind of game is difficult to experience. We had many chances but there were too few goals.
"Maybe the wingers played too high because we absolutely wanted to score and this left space behind for the Finns."