Three things Portugal will have to improve on despite knocking out Croatia

Making the most of being on top

For 45 solid minutes, Portugal were easily the better side. They completely outplayed Croatia and looked far more dangerous when attacking.

In the first half alone, Portugal had 68% of the possession and nine shots - three of which were on target. In comparison, Croatia had only three efforts, failing to test Diogo Costa.

While the Croats were adept at staying calm and composed, it helped that Selecao das Quinas did not do enough while being firmly on top.

The problem was not even that they were not creating chances. It was just a matter of not converting them. These glorious opportunities that came their way will likely become harder to come by in the next round versus Spain.

Failing to utilise the wings enough

A fascinating change in the starting line-up from Roberto Martinez saw Rafael Leao play from the off. From that alone, it was evident that the winger's speed was something Portugal were hoping to make the most of.

And, for quite a while, it did work. Leao was getting past his marker, providing solid deliveries, and looked like a menace every time he touched the ball. 

Leao also combined well with Nuno Mendes, who regularly supported him in the attack. This is something Portugal might want to make the most of going forward. 

However, there came a point where the soon-to-be-departing AC Milan man was not being fed as much. There was a shift, and the regular passes into him suddenly stopped. 

Keeping in mind the good work he was doing, causing the Croatian defence all sorts of problems, perhaps it would be beneficial for Martinez to start Leao again in the round of 16 match. But for that to work, he needs to be getting on the ball more often so he can use his speed and skill to devastating effect.

Defensive shakiness almost cost them

One other thing to note for Portugal was how troubling things looked for them defensively. Sure, Croatia came out in the second half and caused the Portuguese backline problems. But it felt like Kockasti could have scored at will.

Even after going behind, Portugal continued to show frailties at the back. There were a couple of Croatian goals called back for offside, including Josko Gvardiol's stoppage-time finish. On another day, those could have been enough to send them through.

Against a better and more ruthless side, Selecao das Quinas would have been beaten on the night. Quite a bit of luck came their way in this one, particularly from the opportunities they conceded.

Seeing that they will likely have to defend even more against Spain in the next round, Martinez will have to come up with a way to make his side more sound at the back.

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