Richoty Ramsdale
Perhaps given the euphoria of last week's heroic 0-0 draw at Anfield, the shakey start Aaron Ramsdale had to the game was forgotten.
The 23-year-old has been so good for Arsenal this season, that perhaps it was easy to forgive him for having an off day, but seven days on it appeared that not too much had changed.
The England keeper was jittery in the box, lacking his usual composure in the penalty box, often looking to punch crosses instead of catching them, and looking unsure of his positioning when it came to sweeping the ball behind the back line.
Some of the floors in his game were also laid bare by both of Diogo Jota's goals on the night.
The first, demonstrated the issue of getting caught in line with the ball that was previously evident this season for the second goal he conceded in the 2-2 draw with Crystal Palace.
As Jota looked to reverse his shot back towards the near post, Ramsdale had already overcommitted himself to the far, and found himself too flat footed to react to the Liverpool forward's daisy cutter.
Then for the second his eagreness to race out and engage the Portuguese quickly turned a half chance into a golden one for the Reds, and although it appeared the offside flag had bailed him out, VAR ensured the former Sheffield United stopper's luck was out.
Part of the reason Ramsdale was brought in to the Emirates was his ability to come out on top in one-vs-one situations given the high line that Mikel Arteta is hoping to deploy and he has generally been excellent with them so far. But for this one you just wonder perhaps if he's stayed a bit deeper in his goal, then maybe the tie may not have been put out of sight in its closing stages.
It's worth reinforcing just how good Ramsdale has been since his arrival before this appears to be too much of a pile on. His perfectly placed ball out to Gabriel Martinelli on the left in the first half is indicative of just how much he has transformed the Gunners' build up play since arriving.
But it seems as though the excellent form he's shown so far may just be starting to dip a tad.
Perhaps it's due to the firm grasp he's managed to obtain so quickly on the Arsenal number one jersey, with Bernd Leno relegated to second choice.
That may be set to change pretty quickly however.
Reports have suggested that the Gunners are in talks with New England Revolution over American goalkeeper Matt Turner, with Leno set to secure an exit in the coming days.
Fresh competition could be exactly what's needed just to sharpen Ramsdale up ahead of what promises to be a crucial home straight in the race for the top four.
Squad depth issues laid bare
As the team sheet was revealed for this one a sense of an optimistic buzz swept through those who had arrived early at the Emirates Stadium.
All the big names who there had been doubts over were there - Takehiro Tomiyasu, Martin Odegaard, Emile Smirth Rowe, Kieran Tierney all available. Even Thomas Partey was on the bench!
After a fast start it quickly became clear though that the names who have got Arsenal to the stage where their fans are backing themselves against the recent European and English champions were there in body only.
In need of an extra push to maintain the intensity they had shown in the first leg to keep Liverpool at bay, the Gunners were found wanting. This visibly frustrated Mikel Arteta who could be seen throwing his arms in wild indignation as Gabriel Martinelli was slow to press a loose throw in taken by Andy Robertson just before half time.
Much of the 11 who began the game looked as though they had nothing left in the tank and it was little surprise when after the game Arteta revealed that over half of them hadn't even trained before the game.
Contrastingly, Jurgen Klopp's side - without their two best players in Sadio Mane and Mohamed Salah - stepped up a gear to take the lead and then played the rest of the game more or less in cruise control as their superior squad depth shone through.
Realistically though this didn't teach us anything new.
Before Thursday night's game most realistic Arsenal fans would have been aware that, while they had a first 11 capable of competing with the very best, the players to chose from beyond that simply didn't stack up to those at the very elite levels of the game.
Of course the exceptional circumstances of AFCON absentees, COVID cases and unprecedented injuries absentees in specific positions were at play here, but if there's one major takeaway from this match it's that the Gunners still have some way to go before they can challenge for trophies on multiple fronts again.
This was something Arteta was willing to admit himself with something of a thinly veiled message to Edu after the game.
"You need to have a squad of 20, 22 top outfield top players," the Spaniard said. "To do that takes time."
With just 10 days remaining of the January transfer window though the question now has to be can they afford to take there time to get to that level if they want to claim the final top four spot up for grabs.
Arsenal face a midfield crisis... again
For Mikel Arteta finding two available central midfielders to start a first team match has been something of a Sisyphean task. Just as he manages to role the ball up the hill one of his players conspire to ensure that he has to watch it go tumbling back down again.
Last week it was Granit Xhaka whose return from COVID enabled Arteta to field a decent double pivot before the Swiss international was sent off around the half hour mark, and this time around Thomas Partey was the culprit.
The 28-year-old had only arrived in England at midday on Thursday after returning from Cameroon following Ghana's shock early elimination from the African Cup of Nations and was a surprise inclusion on the bench.
With the lack of experienced alternatives on there you got the feeling that he was going to be need at some point, but when he offered to come back and help Arteta, this was probably not what the former Ateltico Madrid man had planned.
Shown his first yellow in the 87th minute, Partey then went on to commit a ludicrous and unnecessary foul on Fabinho on the halfway line just three minutes later before being given his marching orders.
While the dismissal had little impact on the game itself, which was gone by that point, it means that as the Gunners turn their attentions to Sunday's fixture with Burnley, they are again left with Albert Sambi Lokonga as their only senior option in the middle of the park.
Arteta found it impossible to hide his frustration at the actions of yet another one of his senior players in a key moment.
"It’s again a big loss," the Spaniard said. "We have to learn from that.
"We’ve played the last three games with 10 men and against top sides you can’t do that because you’re completely exposed. It’s difficult enough to beat them, but with 10 men it’s then a real challenge.
"It’s not what we need for sure with the amount of players that we have out not to have him."
Martin Odegaard did an admirable impression of a deep lying midfielder looking to receive the ball off the back line and managing the third most touches in the game behind only Gabriel and Ben White, and it's likely he'll be asked to repeat the feat against the Clarets.
Talks to bring Arthur in on loan are persisting with Juventus, and even with only Premier League games left until the end of the season now, you get the feeling the Brazilian will be required regardless as Arteta cannot trust his most experienced players to be available when he needs them.
This is an issue that is likely to be addressed more concretely in the summer, as Arsenal turn once again to the transfer market in order to a problem position into one of strength.
Arteta highlights need for Vlahovic
As much as this was a tie between two of English football top teams right now, it was ultimately one that featured few moments of quality across the two games.
In contrast to the fiery battle at Anfield in the Premier League that saw Mikel Arteta and Jurgen Klopp squaring up on the touchline, these two games were more of a chess match decided in crucial moments.
"I think we had our moments against a top side," Arteta said. "In the first half certainly when we had the chances we hit the bar, and you have to score and in the second half in the beginning it’s the same thing.
"But when that happens that’s difference."
The Spaniard was not wrong.
Liverpool had their two big chances fall to Diogo Jota and the Portuguese forward took them. Arsenal's two big moments on the other hand fell to Alexandre Lacazette and on both occasions the Frenchman was found wanting.
Lacazette has performed an admirably sacrificial role this season, dropping team to facilitate the attacking play of the wide forwards to such great effect that many have argued he should be offered an extension on his contract which is set to expire in the summer. Thursday night though proved why this is not the case.
Up against the might and height of Joel Matip, Virgil Van Dijk and Fabinho, the 30-year-old found himself unable to compete and was dropping so deep to receive the ball that on many occasions the entire Arsenal side was behind the centre circle even when they were in possession.
In the second half he began to try his luck by drifting out towards the right where the Gunners were trying to funnel the ball to Bukayo Saka, but with the lack of a central focal point, the team struggled, leaving Ben White and Gabriel to spend most of the evening knocking the ball from side to side to one another.
Of course speaking in hypotheticals isn't necessarily that helpful, but if Arsenal had secured the signing of Dusan Vlahovic ahead of this game, it's difficult to imagine the Serbian having too many of the same problems.
The 21-year-old is a physical behemoth, who is willing to drop deep, but never lower than the central midfielders, as Lacazette was guilty of doing at times.
Most importantly though, when it comes to those crucial chances in the key moments, Vlahovic is the kind of killer who would have taken them.
Looking at this Arsenal side now, there is little doubting what a clinical striker could do to propel them into the category of trophy challengers. The Gunners need only look down the Seven Sisters Road to see how Harry Kane transformed Tottenham from Europa League also rans to Champions League finalists to see how possible this is.
Unfortunately though it seems as though Vlahovic may be slipping away as a possibility this window at least.
Juventus, have reportedly shown interest in the Serbian, and that kind of competition may be too much for Arsenal to withstand.
That does not change the fact though that if they are to dine at Europe's top table next season, then they will surely need to bring in more at the top end of the pitch.
For all Lacazette's poor play on the night, the man who replaced him, Eddie Nketiah, conspired to do even less to impact procedings.
Flo Balogun has gone on loan to Middlesbrough, while Pierre-Emerick Aubameyang is attracting interest from Saudi Arabia, so if the Gunners want to bolster their offensive options it seems that now is the time.
Whether they are able to do so or not though, remains to be seen.
