Oh how Richarlison needed those goals.
The Brazilian has not been in the best form recently, that much has been clear to Evertonians and to Ancelotti as well.
While the work rate has still been there from the 23-year-old - the usual quality at taking on a man and creating chances for his teammates, as well as scoring them himself, has been lacking.
Fans were getting concerned. Some were wondering how long it would perhaps be before the influential man was dropped to the bench by his manager.
So the relief from all quarters when the forward's low drive from the edge of the box found the back of the net in the first half was understandably palpable.
The strike was everything that fans are used to seeing from Richarlison, full of quality.
He used Toby Alderweireld as a shield to expertly block Hugo Lloris from having a clear sight of the ball, he delayed his effort to just the right time, and the accuracy of the shot when it eventually came was inch-perfect.
Everton didn't deserve to be in front at that time on the balance of the game, but that strike was worthy of giving any side the lead.
Clearly, it had a huge effect on his confidence too, as his second of the evening eclipsed even that brilliant effort.
When Dominic Calvert-Lewin was forced off early in the second half through injury, it was an understandable concern but presented an interesting and rare opportunity for Richarlison.
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This season, he hasn't had much of a chance to play in the central striking role that he loves, but this was it.
His second goal of the night served as a big reminder of what he can do in that role.
Hanging off the shoulder of the last defender, Richarlison timed his run in behind the Spurs defence to perfection from a great through ball from Gylfi Sigurdsson.
From that point, he still had a lot to do, on his left foot as well, but he made what followed look as easy as if he was in the park with friends.
Richarlison fired a fantastic strike right across the face of Lloris and in off the far post, again giving the World Cup-winning goalkeeper absolutely no hope in denying him.
This was so far away from the player who had struggled for confidence over the last few weeks.
The Brazilian looked back to his swaggering best in those few seconds, latching onto a chance and making himself the man for the big occasion once more.
Cup competitions have actually been somewhat of a saving grace for the 23-year-old so far this season.
He's now up to three in the FA Cup this term, having got the same amount in the League Cup earlier in the season.
Considering he only has two strikes to his name in the Premier League so far this campaign, it's something he still needs to bring to his game week-by-week.
But this can surely serve as a timely confidence boost, if nothing else, to Richarlison.
Having been seemingly lacking in belief in recent weeks in front of goal, he couldn't have looked more assured of himself with that second goal in particular.
Everton fans will have their fingers firmly crossed that this can be the catalyst in the 23-year-old's form turning around.
The Blues will need him at the very top of his game for the rest of this season.