Ronny Deila has told Celtic players that they have to reach the standards of skipper Scott Brown and Kris Commons after the Hoops' stars came to the rescue in the 1-1 Scottish Premiership draw with Motherwell at Parkhead.
The Celtic boss made six changes to his side following their 2-2 Europa League Group D draw with Salzburg in Austria on Thursday night but a lacklustre first half saw them go in at the interval trailing to a 19th minute goal by Well striker John Sutton and with boos ringing in their ears.
Brown and Commons came on for the start of the second half to revitalise the champions, with the Scotland midfielder earning a 67th-minute penalty which last season's top scorer in Scotland converted.
Afterwards, Deila said: "Of course I'm not happy with the result. We deserved to win but we made it so difficult for ourselves with a poor first half.
"We had bad tempo, no passes forward and didn't break them down once in the first half. That's not good enough. In the second half, we had two good subs coming on, they brought energy into the game and we played quite well.
"But you cannot rely on one or two players. We need to get the whole squad up at the right level.
"We need to build leaders out on the pitch, for when Scott and Kris aren't there.
"Maybe six changes was too much. But I don't want to rotate that much, it was just needed.
"We had many players out with injuries, new players coming in who we need to play into shape.
"But of course I worry that we might have more days like this. That is why everybody in the squad needs to improve."
The Norwegian admits the race charge hanging over Aleksandar Tonev, who was taken off at the interval along with Beram Kayal, is "not ideal."
The Bulgarian, on loan from Aston Villa, was hit with an Scottish FA notice of complaint on Friday night after Aberdeen defender Shay Logan claimed he racially abused him during last weekend's 2-1 victory for Celtic at Parkhead.
Tonev has been summoned to a principal hearing on October 9.
Deila said: "Yeah, it's not ideal. It takes energy from you. But I don't think this will cause any problems. I believe in him, I believe It's something he hasn't done."
Motherwell manager Stuart McCall was "ecstatic" after the game, not least with Well's first goal at Celtic Park in four years.
He said: "It was a great goal, a good breakaway. We came with a plan to try to frustrate Celtic because you can't be too open."
McCall thought referee Brian Colvin was generous in awarding Celtic a penalty when Josh Law was adjudged to have pushed Brown and claimed Well should have had a spot-kick themselves at 1-0 when Iain Vigurs' shot was blocked by Jason Denayer.
He said: "If it is a yard then fair enough but there is four yards in it when Vigurs shoots and it hits Denayer in the elbow and as I said it was a good save. We were unfortunate that we didn't get it."