Celtic fell to just their second domestic defeat of the season in the final Glasgow Derby at Ibrox on Saturday.

After wrapping up back-to-back titles at Tynecastle last weekend, Ange Postecoglou took a rare opportunity to test some of his fringe players in the toughest domestic fixture without the threat of any discernible consequences on the outcome of the season.

However, as the manager said following the disappointing defeat in Govan, "you don’t get a freebie" at Celtic and he will not have been encouraged by what he saw from some of his squad.

At the back, both Anthony Ralston and Yuki Kobayashi had difficult afternoons as they continued to deputise for injured duo Alistair Johnston and Cameron Carter-Vickers.

Postecoglou also handed opportunities to three more squad players at the expense of three regular starters, a move that, given the outcome, backfired somewhat.

Here, we focus on the performances of those three fringe Celts who were given their chance to impress on the big stage and assess where it leaves them going forward.

Alexandro Bernabei

The first of the three ‘unforced’ changes that Postecoglou made, Bernabei came in for Greg Taylor at left-back for his first derby start.

The Argentine has played the role of backup to the impressive Taylor since he arrived from Lanus last summer for £3.75m and did little to suggest that will change anytime soon.

There was no shortage of energy from Bernabei though – he registered the most pressures (25), and counterpressures (6) of any player in green and white while he also got forward to link up well with Jota on a couple of occasions.

However, his use of the ball was erratic at best and he struggled to progress the ball in busy central areas.

Without Taylor’s greater effectiveness in ball progression from left-back, Celtic found it much more difficult to get into their usual rhythm at Ibrox.

Bernabei still has a lot of great qualities but his tendency to turn over the ball – he was dispossessed the joint-most in the Celtic team on Saturday (four) and dribbled past the joint-most (two) – coupled with his inability to offer the same effective ball progression as Taylor will likely see him remain backup for the foreseeable.

Longer term, there are still question marks regarding his overall suitability for Postecoglou’s system. Given the sizeable outlay, and some of the more encouraging areas of his game, he may yet be offered a little more time to adjust.

Liel Abada

The second ‘rotation’ change was the inclusion of Israeli winger Liel Abada at the expense of Daizen Maeda.

Maeda and Jota have been Postecoglou’s go-to wide men for most of the season with Abada finding opportunities for an extended run in the team hard to come by.

Just back from a hamstring injury, he was given the chance to impress in a fixture in which he has had plenty of big moments previously. Although he had some flashes again, setting up the chance for Oh Hyeon-gyu that hit the post, threading a nice ball through into the box for Matt O’Riley and also having an effort at goal in the box blocked, his overall performance flattered to deceive.

It may be harsh, given this was his first start since March, but his weaknesses on the ball, especially in deeper areas, were exposed again.

For all his impressive output in the final third, his inability to consistently beat his man in a standing start and his limitation in longer passages of play has not improved greatly over his two years at Celtic.

In games against Rangers when Celtic are under the cosh, and inevitably in Europe, these flaws become more evident. It didn’t help he was in front of Anthony Ralston on Saturday either.

While he has his strengths, Ralston has limited technical quality and, like Abada, a tendency to be rigid in his positioning. Their pairing gave Celtic little fluidity on the right-hand side.

As with the loss of Taylor’s effectiveness in possession compared to Bernabei, the inclusion of Abada also meant the loss of Maeda’s sizeable impact off-the-ball, something which has been vitally important in recent derby games.

With reports that Celtic are willing to accept an offer of around £10m for the winger and sizable interest from around Europe, this may well have been the Israeli's final derby outing.

Given his success in the fixture previously, if this was to be his last game against Rangers, it certainly marks a disappointing one to go out on.

Oh Hyeon-gyu

The final squad player to be given a big-game audition at the expense of a regular starter was South Korean striker Oh.

The 22-year-old already knows replacing the talismanic Kyogo as Celtic’s first-choice centre-forward is a sizeable task but his performance showed he still has a way to go to challenge the Japanese marksman consistently.

With just seven touches and one solitary pass in his 63 minutes, it is safe to say he struggled to make his presence felt on his first derby start.

It could have been very different for him, and Celtic, had he taken the one big chance that came his way.

Just minutes after Rangers took the lead, Abada played Oh through on goal. With Rangers goalkeeper Robbie McCrorie stumbling as he came out of his goal, the former Suwon Bluewings striker had the opportunity to quickly level the game.

His clipped effort struck the outside of the post though. Slightly unlucky perhaps but as the rest of the match panned out, this served as a reminder that making the most of these opportunities when they come your way in these games is imperative.

Having just joined in January, and the fact Kyogo himself failed to impact the game himself when he replaced him, the young forward does get a bit more of a pass than the other two.

He will still feel that this was an opportunity missed, in more ways than one.

Conclusion

After confirming a second title in a row with four games to spare, Postecoglou earned the right to experiment with his side at Ibrox at the weekend.

In terms of the result and performance he got though, he may well regret making quite so many changes.

That said, he will have learned some valuable lessons about the level that a few members of his squad are at when it comes to these bigger games.

In that respect, as difficult as it may have been to watch for fans, his selection choices on Saturday may well have been the right ones in the long term.