A combination of Senegal's strength and the lightning quick Sadio Mane menaced Japan's defence, but the Samurai Blue also demonstrated their cutting edge in a 2-2 draw in Ekaterinburg on Sunday to offer a warning to potential last-16 opponents England and Belgium.
Here in Russia, the Three Lions and Red Devils have enjoyed the luxury of cruising through to the knockout stages of a major tournament with a match to spare, England having crushed Panama 6-1, a day after Belgium swatted aside Tunisia 5-2.
A showdown between the two in Kaliningrad on Thursday will determine who secures top spot and an assignment in Rostov-on-Don, or the mission to Moscow that will befall the runners-up.
Supporters of the two countries can justifiably hope to reach the quarter-finals, as they examine the prospect of overcoming their potential opponents from a wide-open Group H.
Indeed, when charting a possible course through to the latter stages of the event, the teams boasting the likes of Robert Lewandowski, Piotr Zielinski, James Rodriguez and Radamel Falcao might have loomed as more probable obstacles.
Instead it was Japan and Senegal who took early control by winning their opening matches 2-1, at the expense of Colombia and Poland respectively.
They continued to state their credentials when drawing 2-2 at Ekaterinburg Arena, where Mane exhibited the raw speed and work-rate that have made him such a valuable member of the attacking trident responsible for firing Liverpool to the Champions League final.
The forward could be found tearing down either flank throughout the first half, offering a welcome outlet to his team-mates and causing regular problems for Japan's defence, who eventually adjusted to more effectively nullify the threat after the break.
Should Mane come up against England, the wing-backs that have provided Gareth Southgate's team with width and an attacking threat may find themselves engaged in less proactive duties.
At least in Kyle Walker, John Stones and Harry Maguire as a back three, England have more pace than most central defences.
The same, perhaps, cannot be said of Belgium.
With a makeshift wing-back in Yannick Carrasco and two excellent but slightly more ponderous centre-backs, Toby Alderweireld and Jan Vertonghen, alongside the quicker but less gifted Dedryck Boyata or an injury-plagued Vincent Kompany, Mane may fancy his chances of pouncing should lapses occur in the Red Devils' anticipated dominance of possession.
If Japan, meanwhile, are the team to be scouted, a less obvious puzzle will present itself to the analysts. Having been parachuted in to replace Vahid Halilhodzic, head coach Akira Nishino has the Samurai Blue functioning as a balanced, efficient unit.
Mere inches prevented Yuya Osako and Takashi Inui from making it 2-1 after Yuto Nagatomo's brilliant assist to supply the latter for the equaliser to Mane's opener, before Moussa Wague struck to restore his team's lead, completing a move in which Senegal's superior strength - an asset remarked upon by Nishino during the build-up - came to the fore.
Japan, though, refused to give up, Keisuke Honda slotting home to reward the persistence identified by Nishino as the solution to their relative physical deficiencies, and which could yet be put to more good work derailing the last-eight ambitions of England and Belgium.
|Joerger has Kings´ ´full support´, says GM Divac|
|England seal series win over Sri Lanka|
|Butler´s heroics spoil Walker´s 60-point game as 76ers beat Hornets|
|He´s an honest guy – Djokovic defends Zverev after Finals controversy|
|Bonucci boos a ´mistake´ by fans, says Mancini|
|Ronaldo still part of Portugal squad – Santos|
|Santos satisfied as Portugal reach Nations League Finals|
|Howell holds onto RSM Classic lead|
|McLeish optimistic as Scotland zero in on Nations League promotion|
|Luis Enrique rejects criticism of Spain star De Gea|
|Schmidt dismisses Hansen´s Ireland World Cup favourites claim as ´banter´|
|There are always imbeciles – Bonucci hits back at fans after frosty San Siro reception|
|Portugal draw ´a step forward´ despite poor finishing – Mancini|
|Ireland were just too good - Read|
|Thomas at the double as France end losing streak|
|Albania 0 Scotland 4: Forrest double sets up promotion showdown|
|Italy 0 Portugal 0: European champions outplayed but secure Finals spot|
|Sensational Djokovic marches into final|
|Stander lauds Ireland´s ´unreal´ defence as All Blacks are thwarted|
|Dazzling Ireland claim historic All Blacks scalp in Dublin|
|Federer unimpressed with Zverev boos|
|Let´s get it on! Cheika relishing England clash|
|Croatia coach Dalic to speak with Lovren over Ramos remarks|
|Xhaka puts improved form down to ´freak´ Emery|
|De Gea not lacking confidence, says Spain´s Saul|
|Jordan goalkeeper scores from own penalty area in friendly against India|
|Pollard leads Springboks to Murrayfield victory|
|Fired-up Japan taught England a great lesson - Jones|
|Sarries leave it late to down Sale, Bath and Saints win|
|O´Shea fumes at disallowed Italy try|
|Southgate welcomes England selection quandary|
|Reaching Rooney´s England goals record ´definitely possible´ – Kane|
|Debut try for Cokanasiga as England rally to avoid Japan upset|
|Wembley will galvanise ´tired´ Croatia, insists Dalic|
|Zverev apologises for tie-break controversy amid O2 Arena heckles|
|Marquez happy with fifth after damaging shoulder in Valencia|
|Wales crush Tonga in Cardiff|
|Germany should keep faith in old guard - Bierhoff|
|Injured Lukaku to miss Belgium´s Nations League decider|
|Zverev knocks out Federer to reach maiden ATP Finals showpiece|
|Koroibete double maintains Australia´s 100 per cent record against Italy|
|Juventus´ Khedira sprains ankle in training|
|Van Dijk: Ramos is not my type of defender|
|Vinales grabs Valencia pole as Marquez crashes|
|I don´t deserve Ballon d´Or, Mbappe does – Hazard|
|Reed and Willett share lead in Dubai|
|Romagnoli joins long AC Milan injury list|
|Williamson steadies Black Caps after Boult heroics|
|Griezmann targets swift French response against Uruguay|
|Havertz´s future lies with Bayer Leverkusen – sporting director Boldt|
|Socceroos boss Arnold excited for future|
|South Africa triumph on Gold Coast in truncated T20 clash|
|Germany without Draxler for Netherlands game|
|Barcelona confirm Rakitic hamstring injury|
|Rain halts England´s post-tea flourish|
|Australia 1 South Korea 1: Luongo seals late draw for Socceroos|
|Irving thrives on ´peace´ of being in the zone|
|Lloris admits France could have lost by more|
|Dybala impressed by Argentina´s improved spirit|
|Arsenal chief confirms Super League talks|
|Hooker knocks out Saucedo to retain WBO strap|
|NBA wrap: Kyrie Irving sizzles as Celtics beat Raptors in overtime|
|Jimmy Butler aims dig at Timberwolves following 76ers home debut|
|Koeman surprised by dominant Netherlands|
|Southgate rallies England ahead of Nations League decider|
|Chile 2 Costa Rica 3: Waston brace sinks La Roja|
|Tite inspired by Guardiola´s City|
|Argentina 2 Mexico 0: Funes Mori´s header helps to sink El Tri|
|Lovren ready for ´fiery´ England clash|
|Brazil captain Neymar pleased with stern Uruguay test|