Celtic 3-0 Inverness CT: Players to leave Deila's squad in summer
Celtic will slim down their squad in the summer, with manager Ronny Deila challenging his players to show they have the character for a big club.
The Scottish champions secured Start 17-year-old Kristoffer Ajer on a pre-contract agreement this week.
And it has led to claims that Deila is signing too many midfielders.
"Yes, I think so," he said when asked if players would leave in the summer. "People have to show who has the character to deal with these things."
Deila was speaking ahead of a 3-0 win over Inverness Caledonian Thistle during which the introduction of young midfielders Ryan Christie, Scott Allan and on-loan debutant Patrick Roberts breathed fresh impetus into the Celtic attack.
"I agree it is too big now," the manager said of his squad. "It starts with being 100% committed to Celtic and, if you do that, you will get your rewards.
"You see that with Kieran Tierney, with Callum McGregor coming back and Tom Rogic coming through.
"There's lots of players coming through and that's because they work harder.
"But if they get lazy then they are not in the team. That's how it is at big clubs and this is a big club - you have to fight for the jersey."
'You don't get everything right'
One newspaper ran a poll to suggest that few of Deila's signings since arriving in Scotland in 2014 have been a success.
"You don't get everything right," he admitted. "Some can be positive and some can be not so positive, but the most important thing is that you learn from it and we have learned a lot through this time and we are in a good position now.
"These are young players and you need consequences. If you don't develop and don't work hard, you don't have your jersey.
"To get people to progress, you need a big squad, but I think it's a little too big now."
Caley Thistle created the better of the chances at Celtic Park until Gary Mackay-Steven broke the deadlock via a deflection.
"We have to give credit to Inverness," said Deila after his side pulled six points clear at the top of the Premiership. "They are a good football team and they kept the ball and made it hard for us.
"In the second half, we started more positive and were more direct in our play and we got our chances and some good substitutions made a difference.
"In the end, we had more chances than them and deserved to win."
Caley Thistle manager John Hughes was "bitterly disappointed" that his side's efforts came to nothing.
"I am a bit frustrated, but I can't ask more of my boys," he added.
"I just feel for them because we played good stuff and had one or two real good chances.
"They passed it, Celtic knew they were in a game and it was the second goal that killed us.
"Even in defeat, you can take great pride and inspiration from the way we played. We gave as good as we got."