You may not want to but let's cast our minds back to March 2023. Arsenal are facing Sporting in a Europa League knock-out match and William Saliba has gone down injured.
The replacement that day was Rob Holding. Yes, it's remarkable just how much this squad has progressed since that day.
Arsenal's Rob Holding reacts
Holding was a loyal servant to the club but he was never really Arsenal quality. The run-in during the end of the 2022/23 campaign, a season in which the Gunners played some scintillating football, showcased just that.
After that injury on the European stage, Saliba didn't play another minute of the season, which meant Holding was forced into the side. It did not go well at all; the Londoners only won five of their last 11 league matches, missing out on the Premier League title.
Saliba-Arsenal-Sporting
The central defender did score against Manchester City, albeit it that came in a crippling 4-1 defeat a match where Jamie Carragher explained at full-time that Erling Haaland vs Holding was a "physical mismatch."
That sequence of games has been a learning curve for Mikel Arteta and it perhaps still scars him to this day. Arsenal have signed a whole host of defenders since and the way with which they've dealt with Saliba's latest injury setback is a testament to that.
Enter, Cristhian Mosquera.
Cristhian Mosquera's stunning form for Arsenal in numbers
Holding, who? The level of progression from Arsenal's backline since the English centre-half departed for pastures new is remarkable.
The layers of depth Arteta now has at his disposal in defence speaks volumes. At left-back, he can call on Riccardo Calafiori, Myles Lewis-Skelly and Piero Hincapie.
Calafiori-Arsenal
In the middle, he can call on Calafiori and Hincapie again, although right-backs Jurrien Timber and Ben White also possess the ability to play as centre-backs should Saliba and Gabriel be absent.
There will be no more Holding situations, and Mosquera's early-season form in London proves that.
Arsenal's Cristhian Mosquera and Martin Zubimendi
Very rarely can a football player be described as a bargain in the modern market but the £13m that Arsenal spent on Mosquera certainly looks like that.
It wouldn't be a surprise if Valencia phoned the police to report a robbery, that's how cheap his price tag looks.
That's because his latest two outings demonstrate that if Saliba or Gabriel are missing, there won't be a drop off in quality.
When the French central defender hobbled off early on in the defeat against Liverpool, every supporter feared the worst, but Arsenal's new Spanish signing was a match for the likes of Cody Gakpo, Hugo Ekitike and Mohammed Salah.
Yes, the hosts may well have won at Anfield but Mosquera was phenomenal, completing 92% of his passes and winning four of his five duels.
Against Forest, he was arguably even better. Saliba was still missing but his young stand-in, aged just 21, didn't put a foot wrong.
Mosquera Arsenal stats vs Forest
On this occasion, he kept a clean sheet, completed 91% of his passes and lost just one of his four duels. Impressive stuff indeed.
Remarkably, however, the Gunners may well be brewing a bigger talent in the Hale End ranks.
Introducing the best centre-back Hale End has produced
When Arsenal announced the arrival of Mosquera over the summer, Andrea Berta found it difficult to hide his admiration for the young defender: "We identified Cristhian as one of the strongest young defenders in European football, and he is an important signing for our future," exclaimed the Italian.
Well, speaking of the future, there is a world where he could be partnered by one of the most promising talents in the club's academy.
Mosquera-Ekitike-Arsenal-Liverpool
That player is Marli Salmon. Aged just 16, he's already been described as the Max Dowman of defenders and while he is yet to appear in a competitive fixture for Arsenal, he did make his first team bow during pre-season.
Salmon looked miles above his age and really did stand out at the heart of Arteta's backline, featuring against both Milan and Newcastle.
Versus the Italian giants, the young defender played the final 24 minutes of that encounter and completed 94% of his passes. Against Newcastle, he featured for just 13 minutes but once again looked at ease, this time completing 100% of his passes.
He's certainly composed at the back and testimonies from those who follow Hale End more closely indicate that he could well be on Dowman's level.
Max-Dowman-Arsenal
Currently being mentored by Saliba, insider Hand of Arsenal has noted that Salmon is "rated very very highly by everyone at the club," while suggesting that he is "the best centre-back in his age group."
Well, data analyst Ben Mattinson has gone a step further by suggesting that the teenager is "the best centre-back Hale End has produced."
Possessing Saliba-like calmness in possession, Salmon's talent looks immense and it would not be a surprise if we start seeing him playing more first-team minutes in a few years.
He's not quite ready yet, but the fact he went on the club's pre-season tour suggests Arteta likes the look of him. Those reviews suggest he could become an even bigger talent than Mosquera. Exciting times indeed.