Celtic boss Ange Postecoglou will have learned a lot about his fringe players during Saturday's 3-0 Scottish Premiership reverse against Rangers on Saturday.
The champions slipped to only their second defeat of the league campaign to Michael Beale's men at the weekend.
Postecoglou made six changes to the side that clinched the title at Tynecastle last weekend as Anthony Ralston, Alexandro Bernabei, Liel Abada and Oh Hyeon-gyu were all handed a start at Ibrox.
The bigger picture for the Australian will be what lessons he can take from the individual displays of those he trusted to do battle in Govan but ultimately came up well short.
As he admitted: "It does (have an impact) when you change things. It is a tough place to get an opportunity, but it is not the first time certainly I’ve done that and sometimes giving guys debuts in these games... they just need to understand what this football club’s about. That’s the expectation.
"You don’t get an easy ride, you don’t get a cushy introduction into life as a footballer. It is demanding from the moment you put on a shirt to the moment you leave.
"It is fair to say it wasn’t just about the guys who came in. Obviously the changes didn’t help but I just thought the general performance, and the level of performance, wasn’t there.”
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The defeat was branded unacceptable by Hoops skipper Callum McGregor while Ralston admitted that Celtic had no excuses.
It was the proverbial bad day at the office for the visitors at Ibrox.
Celtic can console themselves with the thought that they are homing on a world record eighth domestic treble during a season of unprecedented highs.
The silver lining on a poor performance at the weekend duly arrived in the form of the PFA Scotland awards where Celtic swept the boards.
Postecoglou scooped the Manager of the Year award while Kyogo Furuhashi lifted the Player of the Year award and Jota won the Goal of the Season award for his impudent chip against Rangers during the 4-0 triumph at Celtic Park back in September.
Join Tony Haggerty and Ryan McGinlay as they discuss all this and more in the video below.
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