Some big decisions faced Frank Lampard on Saturday before Everton took on Manchester United. Having seen his side crumble at Turf Moor just a few days previously, it was always going to be a monumental task to try and pick them off the floor and go again.
The act of doing that meant that there had to be changes to the starting line-up, that was inevitable. With players returning from suspensions and other absences, there was a lot more for the manager to play with to bolster his starting 11.
But, interestingly, clearly there was a desire for the overall system to stay the same. The West Ham match brought something of a 4-1-4-1 style to Everton, with Mason Holgate sitting in front of the back four as a defensive midfielder, which continued into the Burnley defeat - despite another loss at the London Stadium.
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Lampard clearly felt he had hit upon something useful. All he needed was the right personnel in important areas of the pitch, with the midfield in particular seeing some crucial switches for the visit of Manchester United to Goodison Park.
Allan, who had been absent since his sending off against Newcastle, was brought back into the side to play in front of Fabian Delph who took Holgate's position as the sitting midfielder. Meanwhile Abdoulaye Doucoure, who's been a regular starter since he made the move to Goodison, was dropped to the bench.
Already that's a big call in itself. Granted the Mali international has not been playing at his best, or arguably anywhere near it, in recent weeks, but so often his energy and quality can prove to be the difference, especially when he's partnered with Allan.
The Brazilian replacing his teammate, however, allowed him to take up a more advanced role which is something a lot of supporters have been crying out for. While he can play as a defensive midfielder to good effect, at Napoli he was instead utilised in this position further up the pitch - often hunting down possession when off the ball and using his great skill as a ball-carrier when his team are in the ascendancy.
Evertonians certainly got a glimpse of that on Saturday afternoon, with Allan taking just 30 seconds to receive the ball deep inside his own half, before playing a splitting pass down the pitch which cut out the entire Manchester United midfield and set the hosts on the attack. That kind of direct and purposeful passing is something Lampard's squad have sorely missed recently.
And, of course, he still showed that defensive ability that Blues supporters have come to expect. Only this time, he had the freedom to roam a little more with the knowledge that there was still adequate cover in behind him.
According to statistics from FBref, Allan made more pressures than anyone else on the field for Everton with 37, beating his closest competitor in Richarlison by a clear eight. Only Vitalii Mykolenko made more tackles than his four, while Anthony Gordon alone boasted more blocks than his four.
The transformation that he brought to his side was clear to see and helped them get the upper hand in the centre of the pitch, something they haven't been able to do often this season. But, it wasn't just his influence of course.
Delph took over from Holgate in defensive midfield, with the natural centre-back bowing out of the starting line-up having played fairly well in that position given the circumstances. It's certainly not his preferred role, though, and his replacement on Saturday showed exactly why.
The former Man City man was absolutely everywhere Everton needed him to be against Manchester United, whether in or out of possession. His positioning was exemplary, making sure he only needed little bursts of pace at times to get into place for a pass or to cut out an opposition attack.
When the defence found itself in possession, Delph would often drop backwards to make sure he could either collect the ball or drag a Manchester United player out of a crowded centre circle, leaving space for either Allan or the excellent Alex Iwobi to receive possession. Little details such as that are the difference between a natural defensive midfielder, and someone just filling that role.
He made some crucial tackles and interceptions throughout the game and, importantly, his short passing was excellent. Too often this season Everton have lost the ball cheaply in the centre of the pitch leaving them exposed, but that never felt like a danger with Delph's assured presence on the ball.
So, where does that leave Lampard? He's certainly found something good with this personnel in this system, but is that going to be the case for the long-term?
This summer is going to be absolutely crucial for the Blues whatever division they find themselves in, and both players who came into the midfield on Saturday have interesting questions ahead of them. Delph is out-of-contract at the end of the current campaign, while Allan is already facing some speculation about a potential move away.
What the manager must first decide is whether this is a system he sees himself using more often in the future at Everton. If there is to be a squad overhaul in the summer, the club could find itself with a completely different balance heading into 2022/23, leaving a different formation as a more viable option in the long-term.
Delph and Allan proved themselves crucial against Manchester United, but perhaps the boss and director of football Kevin Thelwell need to focus on the deeper reasons as to why that was the case. What about their profiles as individual players made them so good for the rest of the side, and can that be replicated with a viable signing from elsewhere?
You feel this is particularly relevant in Delph's case. This was a fantastic performance from him, there's no doubt about that - but the rest of his time at Everton has proven that they can hardly trust his injury record when it comes down to it.
If a new deal can be negotiated at a price that works for the club that could certainly be more palatable, but regardless the Blues would need to hope for a better output in terms of playing time than they have had since his 2019 move from Man City. There can never be any guarantee of that, so any decision would likely be a risk.
For Allan, Everton have perhaps not used him in Saturday's position as much as they should have done. The Brazilian can be a fantastic option in that area of the pitch is there is a regular defensive midfielder behind him, and that will no doubt be the reason why many fans want to see him stay for next season and beyond.
Regardless, Saturday's win over Manchester United was proof that a three-game transformation of the Blues' midfield could actually work for Lampard. It could be a real turning point at a crucial stage of the season if they can continue the trend they have now set.
