Morocco’s victory over Spain was the most engaging match of the Round of 16, and one of the best of the tournament. After a group stage that saw numerous upsets, it was the sole victory by an underdog despite Morocco being the first-place finisher.

There was some speculation that Spain were happy enough to allow Japan to take first in their group, but if so it was almost certainly a miscalculation. Morocco’s defensive prowess had been demonstrated in the group stage, and against both Croatia and Belgium (particularly the former) they had demonstrated their effectiveness at frustrating possession-oriented opponents like Spain. Moreover, the overwhelming crowd support for the Atlas Lions made this encounter a genuine home game.

Morocco’s line-up and tactics were as expected: a counter-attacking 4-3-3 set in a mid-level block (between the midline and 30-35 yards from goal), often described as a 4-1-4-1 to emphasize Sofyan Amrabat’s defensive role in between the lines. While the frontline of Sofiane Boufal, Youssef En-Nesyri, and Hakim Ziyech offers serious counter-attacking threat, recently appointed Walid Regragui’s side is really built around its midfield and defense, and on the defensive contributions of those attackers.

After making eight changes for their final group stage game, Luis Enrique returned to his 4-3-3 starting XI for Spain’s opening two matches–with one exception. With right back César Azpilicueta suffering from a thigh injury (or calf, in some reports), Enrique opted to replace Real Madrid’s Dani Carvajal at right back with Atlético Madrid’s center-back/midefielder Marcos Llorente. Not unlike his broader decision to use midfielder Rodri as a center back to facilitate passing from the back line, the choice of Llorente, who frequently plays on the right of a back three, suggested that Enrique wanted a third option for breaking down Morocco’s defensive block from the top.

Clearly, that did not happen. Spain’s best chances of the first half came less from their patient passing than from pressing (as in Olmo’s 25′ interception of keeper Yassine Bounou’s pass out to Hakimi) or from the rare ball over the top (for Asensio at 26′). Moreover, Morocco was able to capitalize on Llorente’s presence in their own counter-attacking. While pre-match analysis had focused on the threat of PSG’s Achraf Hakimi and Chelsea’s Ziyech up the right, it was Boufal who consistently had the beating of Llorente down the left, and created much of Morocco’s first half threat.

Just how much threat was made clear when, for the final 15′ of the first half, Pedri González was called upon to drop in as a de facto left back, Llorente pushing forward into a compensating midfield role (with Gavi Martín moving to Pedri’s original position on the left of midfield). Enrique seemed to have briefed Pedri, who typically plays on the left of midfield, to help out defensively with the threat down that flank; but it ended up being the right rather than the left where his services were needed.

In the second half, Llorente had returned to the right back role, but Pedri remained on the right side of midfield to add defensive support until Carlos Soler came on in place of Gavi shortly after the hour mark, freeing Pedri to return to the left. Initially, he too played as de facto right back with Llorente on the right of midfield; but fairly quickly Soler moved into the midfield role, with Llorente returning to right back.

By that point, Enrique finally seemed to be thinking about tweaking Spain’s attack rather than their defense. Along with Soler, Álvaro Morata replaced Marco Asensio up top, a player whose omission had raised almost as many eyebrows as Llorente’s inclusion. Though no traditional target man, Morata is a center forward comfortable running in behind center backs; and he had scored in each of Spain’s group stage matches (albeit as a sub in two of those games).

Whether because of these changes or simply from the weight of defending Spain’s relentless tiki-taka for an hour, Morocco’s line dropped into a lower block, resting just above their penalty box. With 15′ of regulation remaining, Enrique brought on Nico Williams for Ferran Torres at right wing. His impact was immediate, bursting behind Morocco’s defense and delivering threatening balls in.

With just under 10′ remaining in regulation, Regragui made four changes of his own, the last of them forced by an injury to center back Nayef Aguerd, who had looked impressive throughout. The most noticeable was Walid Cheddira, who replaced En-Nesyri up top and almost immediately had a chance off a Hakimi cross to the far post headed back in by Abde Ezzalzouli (who had replaced Boufal shortly after the introduction of Soler and Morata). He had Ziyech unmarked at the top of the box and should have laid it back to him, but instead attempted to turn his defender and for an easily-saved effort. Cheddira plays for Serie B side Bari (and scored a hat trick against Hellas Verona in an opening round Coppa Italia win back in August), but has been linked with a transfer to Nottingham Forest.

Notwithstanding that chance, Spain were the more threatening side as regulation wound down, as Morata headed a Soler free kick narrowly over the crossbar and Rodri dummied a Dani Olmo free kick to the far post to force an excellent save out of Bounou. The same was largely true of extra time as well, as Cheddari again had chances that came to nothing while Spain threatened.

Near the end of extra time, both Spain and Morocco brought on penalty takers, Pablo Sarabia and Badr Benoun. Sarabia very nearly ended the game before penalties, putting in a dangerous cross at 120′ cleared by Augerd’s replacement, Jawad El Yamiq (on television it looked like a potential own goal, but the reverse angle revealed it was a safe clearance) and then hitting the post with a narrow-angle shot at 122′.

Despite Spain’s greater threat in the latter stages of the game, this was a deserved tie for Morocco, who had employed an excellent tactical approach and had never looked without threat themselves. Amrabat was the man of the match, controlling the midfield and taking on whatever defensive job was needed to keep Spain at a distance.

The shoot-out was not so close as the game had been. While only Benoun failed to score for Morocco, Sarabia hit the post and Bounou saved both Soler’s and Sergio Busquets’s efforts. That allowed Hakimi, a Madrid-born Real academy product who had turned down inquiries from Spain to play for Morocco, to score the winning penalty. It was a magical moment for the fourth African (and first North African) side to make the quarterfinals.

NOTE: An earlier version of this blog incorrectly identified Atlético Madrid’s Marcos Llorente at Leeds United’s Diego Llorente.