Scottish champions Celtic slipped to just their second league defeat of the season away to bitter rivals Rangers on Saturday afternoon, with the home side clinching a deserved 3-0 win courtesy of goals from Todd Cantwell, John Souttar and Fashion Sakala.
In the aftermath of that disappointing derby display, Hoops boss Ange Postecoglou may well be ruing the enforced changes to his side for the trip to Ibrox, with the backline, in particular, having looked somewhat makeshift with both Alistair Johnston and Cameron Carter-Vickers missing out through injury.
The absence of the latter man allowed January arrival Yuki Kobayashi to make just his sixth appearance for the club, although the Japanese centre-back looked somewhat shaky at the heart of the defence, having been 'out of his depth' according to Football Scotland's Mark Hendry.
The 22-year-old was notably beaten in the air by the aforementioned Souttar for the Light Blues' second goal of the day, while Glasgow Live's Will Lancaster noted that the former Vissel Kobe man was 'generally nervy' on what was his debut Old Firm outing.
That below-par performance – in which the new man won just four of his 11 duels and lost possession on 18 occasions – was a key factor in the end result, although Kobayashi wasn't alone in having let Postecoglou down, as fellow defender Alexandro Bernabei also failed to take his big chance.
How did Bernabei perform against Rangers?
Having been given the nod over Greg Taylor at left-back, Bernabei also proved something of a defensive liability alongside Kobayashi, having looked 'uncomfortable' and 'unsettled' throughout, according to the aforementioned Hendry.
One notable gripe that both Postecoglou and supporters will have with the young Argentine is his wasteful nature in possession, as the 22-year-old lost the ball on 28 occasions from his 100 touches, having regularly played the visitors into trouble.
There's no doubt that the £3.75m man certainly gets stuck in – as he won 11 duels on the day – although the tenacious full-back can seemingly be got at at times, having been dribbled past twice against Michael Beale's men.
As Lancaster also suggested, the former Lanus menace also 'failed to show his strong attacking qualities' despite completing four of his six attempted dribbles, with Anthony Ralston having offered a greater threat on the opposite flank after registering two key passes.
Bernabei's all-round woes were notably showcased by the fact that he recorded a measly match rating of just 5.9, as per Sofascore – the worst of any player for either side – with usual starter, Taylor unlikely to be fearing for his place in the side in the long-term.