Even though Barcelona are going through a stuttering patch of form, the performances of Messi have remained largely positive. He was their best player in the loss versus Valencia without scoring, but he did get back on the scoresheet with two strikes, as well as an assist, against Leganes.
He actually played a part in the opening goal, too, earning a 'pre-assist' as it was his pass to Nelson Semedo which allowed the Portuguese to assist Antoine Griezmann.
Midway through the first half, he would then whip a corner to the front post for Clement Lenglet to glance a header home.
The Argentine would then score his first, albeit in fortuitous fashion as he sent a deflected strike up and over the goalkeeper after going on a signature twisting and turning dribble in from the right. His second was the better of the two, as he burst through on goal to take a touch round the keeper before lashing a finish into the roof of the net.
Martin Odegaard's outstanding form translated from the league to the cup as he scored one and assisted two more goals against Osasuna.
The first goal was scored by Alexander Isak via a precision corner from the Norwegian, who caused problems all game from his set-pieces. Indeed, it was one of his set-pieces which got him on the scoresheet as he sent a free-kick up and over a weak Osasuna wall into the bottom corner from 25 yards.
No surprise then that it was another set-piece which led to the third, as he once again assisted Isak with a corner.
In terms of passing, he completed 48/55 attempted balls to team-mates.
The German was comfortably the best player on the pitch, and set up the first two goals for Madrid, first with a low, drilled cross to the back post for Raphael Varane to tap home and then with a threaded pass into the box, with Lucas Vazquez the beneficiary then.
As usual, his passing was remarkable, as he completed 99/104 balls for a completion rate of 95%, while he enjoyed 11 touches overall.
It takes a lot for Kroos to be outdone in the passing department, but even his numbers were dwarfed this midweek by Barcelona's Clement Lenglet, who completed a sensational 122/125 balls to team-mates during his time on the pitch.
As well as ensuring that the Blaugrana played out from the back with composure, he was a threat at the other end, too, as he scored Barca's second with the aforementioned header at the front post after the assist from Messi.
It says a lot about the attacking prowess of Leganes that he made it through the entire match without making a single tackle.
The surprise of the round saw Mirandes eliminate Sevilla after a 3-1 win at home, with the scourge of the Rojiblancos proving to be Matheus Barrozo, who scored two of the three.
He proved to be a nightmare for the opposition defence all day, and it would be his two goals which would give Mirandes a two-goal lead in the first half. HIs first goal was superb, as he displayed a cracking first touch, as well as some impressive strength, to swivel inside the box to fire a strike into the top corner.
There was a definite element of luck with the second as his strike from range was deflected past the hapless Tomas Vaclik in goal.