Portugal head into their Group B showdown with Morocco on Wednesday still on a high after Cristiano Ronaldo's late free kick secured a 3-3 draw with Spain.
As for Morocco, Herve Renard will have had to work hard to lift his players after they succumbed to a last-gasp defeat to Iran in their opening fixture on Friday.
Portugal
For the first time in many years, Portugal head into a major tournament regarded as more than dark horses due to their triumph at Euro 2016, and their performance against Spain will only add to the theory that they can achieve a famous double.
After injury cut short his time in the European Championships final, Ronaldo appears to have arrived in Russia knowing that time is running out to add the Jules Rimet trophy to his vast list of accolades, and that desire will strike fear into future opponents.
When the Real Madrid superstar stepped back to take that late free kick against Spain, there felt an inevitability about what was to come, and it is a moment which can act as the springboard for Portugal to have a long run in this competition.
Publicly, Ronaldo will say that he does not see himself in direct competition with Lionel Messi but with the Argentine maestro failing to impress against Iceland at the weekend, it will only add to the theory that Ronaldo is determined to outshine his biggest rival.
Despite the heroics of the 33-year-old, Portugal cannot afford to ignore the negatives from Friday's performance, most notably a defensive performance which will only encourage Morocco and Iran.
Fernando Santos is dealing with a transitional period with his backline, and with veterans Pepe and Jose Fonte both showing their weaknesses against Spain, the national team coach must decide whether to draft in younger replacements.
The same pairing kept a clean sheet against Belgium earlier this month, but A Selecao das Quinas have only recorded two shutouts in their last seven outings and it is an area of the pitch which could potentially undermine their efforts in the final third.
Games with Morocco and Iran give Santos some leeway to find a stronger solution in the long term, but a balance must be found at a time when achieving first place in Group B could prove to be crucial.
Recent form: WLDDWD
Morocco
Morocco would have started this tournament knowing that they would probably need victory over Iran to have any realistic chance of progressing through to the last 16, with even a draw giving them an outside opportunity.
However, the 95th-minute own goal from Aziz Bouhaddouz which gifted Iran all three points in St Petersburg has left Renard's side having to pull off the unthinkable to earn a spot in the knockout stages.
Morocco will still hold an inner belief and a desire to impress against Portugal and Spain, but the African nation need to pull off two of the great World Cup shocks to maintain any chance of remaining in this competition.
In terms of shots on goal and possession, there were positives to take from Friday's contest but Renard needs a reaction from a squad which holds the necessary experience not to be overawed by the clash in Moscow.
Juventus centre-back Medhi Benatia was superb against Iran and the 31-year-old will be called upon to deliver a captain's performance against Ronaldo, while young full-back Achraf Hakimi will relish the chance to try to nullify the threat offered by his Real Madrid teammate.
Further forward, Ajax's Hakim Ziyech will need to show more of a clinical touch in the final third to add to his nine goals from 19 outings for his country, but they key battle could come in midfield, with Mbark Boussoufa and Karim El Ahmadi - formerly of Chelsea and Aston Villa respectively - needing to roll back the years.
Combined with losing the bid to host the 2026 World Cup, it has been a rough few days for Morocco but this is a squad which is unlikely to accept the general consensus that they have little hope of qualification.
The Atlas Lions may need a bit of luck to get their first point on the board, but Portugal have not always relished the group-stage section at major tournaments and opportunities could materialise in Russia's capital.
Recent form: WWDWWL
Team News
Goncalo Guedes will be hoping to keep his place in the Portugal team, but the Paris Saint-Germain winger faces competition from Ricardo Quaresma.
Joao Mario - who spent the second half of the season on loan at West Ham United - will also hope to feature if Santos opts for a more offensive-minded strategy.
Santos may take the chance to rest one of Pepe and Fonte, with Ruben Dias waiting in the wings to make his second appearance for his country.
Morocco will make at least one change, with Nordin Amrabat being ruled out of Wednesday's game due to a concussion sustained against Iran.
Younger brother Sofyan Amrabat could take his place in the team.
Portugal possible starting lineup:
Patricio; Soares, Pepe, Fonte, Guerreiro; Carvalho, Moutinho, Mario; B.Silva, Guedes; Ronaldo
Morocco possible starting lineup:
Munir; S.Amrabat, Benatia, Saiss, Achraf; El Ahmadi; Belhanda, Harit, Boussoufa, Ziyech; El Kaabi
Head To Head
Wednesday's fixture will represent just the second time in which these teams have met on the international stage.
That match took place at the 1986 World Cup, with two goals from Abdelrazze Khairi helping Morocco to a 3-1 victory.
We say: Portugal 3-0 Morocco
Morocco possess players who can challenge Portugal on Wednesday, but we expect the European champions to come through with something to spare. The battle is on with Spain to end the group stages with a better goal difference, so Ronaldo and co could be at their ruthless best.