Russia got their World Cup campaign off to a dream start with a 5-0 thumping of Saudi Arabia but face an entirely different beast in the form of Egypt, who should be revitalised by the return of their talismanic striker Mohamed Salah.
The hosts face the north Africans in St Petersburg on Tuesday and defeat would almost certainly condemn Egypt to an early exit.
Russia top Group A on goal difference ahead of favourites Uruguay, who needed a last-gasp goal to scrape past a dogged Egypt 1-0 in their first game of the tournament.
Egypt, coached by Argentine Hector Cuper, are still targeting a second-placed finish in the group, but must beat Russia to have any hope of achieving that goal.
Cuper's team showed against Uruguay they will not defend as generously as the hapless Saudis, and Salah, who should make his first start, will relish the chance to torment Russia's aging defence.
Coach Stanislav Cherchesov started centre back Sergei Ignashevich, 38, and full back Yuri Zhirkov, 34, in the first match, and if the Russia coach sticks with the same duo, Egypt and Salah could capitalise.
The 26-year-old's birthday was ruined by the Uruguay defeat and he spent the match on the bench as Cuper elected not to risk his star man, who is making his return from a shoulder injury.
While Zhirkov still has plenty of pace, he will find it hard to cope with the lightning-quick Salah, who cut a swathe of destruction through European defences for Liverpool last season while coming in from the right wing on to his lethal left foot.
Ignashevich's experience is an asset but his age counts against him and any attempt to double up on Salah will free up Mahmoud Hassan, better known by his nickname "Trezeguet", on the opposite flank.
The 23-year-old proved to be a handful against Uruguay and Russia's Brazil-born right back Mario Fernandes will need all his wits about him to keep Trezeguet quiet.
While Egypt are strengthened immeasurably by Salah's return, Russia will be weakened by the absence of creative midfielder Alan Dzagoev, who was injured during their opening match.
Dzagoev was replaced by Denis Cheryshev, who earned himself instant cult status with a well-taken brace.
After entering the tournament ranked a lowly 70th in the world, expectations around Russia were subdued, with many fans believing the team might prove an embarrassment.
The opening win has put those fears to rest, but the confidence now flowing through the Russian ranks could be their undoing.
Egypt are set up to play on the counter-attack, with Cuper asking his midfielders and defenders to stick close together in two rigid banks of four and restrict the spaces that opponents seek to exploit.
The game plan is simple - get the ball into Salah's feet quickly and let him do what he does best.
If he is match fit, Russia will be hard pressed to stop him helping Egypt to their first victory at a World Cup.
'Spain have mentality to overcome Lopetegui turmoil'
'Strangest' moment of this footballer's career...
How Russia team is fuelled by pre-World Cup criticism...
Why few England fans are making trek to Russia
Croatia's Modric ready for Argentina challenge