Brendan Rodgers says Celtic "have to put right" their recruitment strategy as the manager believes transfers take "a lot longer" than he would like.
In his pre-match interview with BBC Scotland ahead of Sunday's 3-0 defeat of St Mirren, Rodgers revealed midfielder Matt O'Riley was on the verge of joining Brighton for what is expected to be a substantial fee.
He hopes to be given some of those funds to strengthen his squad in the final week of the transfer window but stressed that an overhaul of the current policy will be required regardless.
"There are a number of things I won’t go into here, but it’s definitely something, having come back in and gone through three windows now, we have to put right as a football club," Rodgers said.
"We shouldn’t have been getting into this last week in the position we're in. That's the reality. However, that's something for us for after this window."
Rodgers has brought in goalkeepers Kasper Schmeichel and Viljami Sinisalo this summer, while striker Adam Idah and midfielder Paulo Bernardo have completed permanent moves after last season's loan spells.
However, he has talked of the need, in particular, for extra cover at left-back, central defence, up front and now two midfielders to compensate for O'Riley's exit.
"As I said, we'll get the players in that we want - we don't need to manufacture our own stress when there's no need," he said.
"That’s the reality. However, that's something for us for after this window. We want to develop, we want to improve. We can't be happy just to make our money and build our pot because the bottom line is on the pitch."
Rodgers believes the club owes it to the supporters to build on their success.
"The supporters, they pay the money," the manager said. "I look back to the Covid times here, the Celtic supporters sold the stadium out and they weren't allowed in it, so we have the duty to put the best team on the pitch.
"We can do it by Friday, strengthen the squad, we’ll be in a really, really good place, but we want to strengthen and have that depth. It's taken a lot longer than I would have liked as the football manager."