Croatia coach Zlatko Dalic believes his team lacked "courage" as they were held by Morocco in their World Cup opener, with Luka Modric offering a similar opinion.

The 2018 runners-up were big favourites to claim an opening-day win that would have been big step towards progression from a group that also features Belgium and Canada.

While Croatia enjoyed just shy of 65 per cent of the ball, they only managed to craft two clear opportunities at Al Bayt Stadium on Wednesday.

The first, a prodded Nikola Vlasic effort, was saved well by Yassine Bounou at the end of the second half, and just before the break Sofyan Amrabat made a vital block to keep Dejan Lovren's attempt out of the bottom-left corner.

Nevertheless, their accumulative expected goals figure of 0.66 highlighted a general lack of attacking authority, which Modric was eager to point out.

"We'll be better, we need to adopt a more proactive attitude and pass the group, that's our primary objective, to qualify," Modric told reporters.

"We had a great defence, what we were missing was a goal. We'd have had more luck if we'd had a more proactive attitude."

It was put to Dalic that Croatia underwhelmed considering their greater share of possession and he did not disagree.

He added: "You're right when you say that regarding ball possession and control. Our opponents were good, compact, and faster than us sometimes.

"They were behind our midfield and wingers, so we had a problem with making [attacking] passes.

"We should've gone forward more. We were afraid of counters, we were cautious about mistakes and indecisive.

"A bit of courage was missing on our part. We had control but not enough opportunities or decisiveness. We didn't go forward as much as we wanted to."

Perhaps predictably, Croatia's journey to the 2018 final was soon brought up, but Dalic felt it was irrelevant to start comparing the two squads and insisted Wednesday's disappointment will not alter their ambitions of going far.

"We cannot draw comparisons between the two generations," he said. "It's difficult to draw comparisons between the generation of four years ago and this.

"We know we have competence and we are prepared to fight. We will not be deterred and won't be stopped in our ambition. We are moving on; tomorrow is another day and that's it. This is going to be a tough tournament, for sure."

A point certainly appeared a better result for Morocco than it did for Croatia, even if the Atlas Lions are still searching for their first World Cup win since 1998.

There rarely looked to be any danger of Morocco stealing a victory, though, with Dominik Livakovic in the Croatian net barely troubled.

Morocco coach Walid Regragui disagreed with the suggestion his side lacked bravery, however.

"Not exactly because we wanted to win, but the strategy worked. We played like a European team. Morocco managed to create chances, and in fact we played a balanced way, a solid way, and it was difficult for Croatia.

"It was not fear. We see that this was only our first match. Maybe we could've played better, but we take every match as it comes, and still I know we should be in possession more and adapt to each opponent.

"I think the possession was 65 per cent for them, but I think when we had it we were more efficient. We'd have preferred that we had a different outcome but still I think we did well."