Given Gareth Southgate's penchant to inject the England midfield with creativity and his desire to play both Dele Alli and Jesse Lingard in more advanced roles, it means one of his trusted protectors will miss out, with Southgate admitting that he wants "to play with one 'pivot'."
In the past, England have typically deployed a 4-2-3-1 formation, with both Henderson and Dier starting in a defensively minded double pivot. To avoid tentativeness in possession and a lack of incisiveness, this has been scrapped in place of a more attacking formation.
I would be amazed if the two of them are not important figures for us during the tournament, but there is clearly the possibility they might not both play in every match. - Gareth Southgate.
This will see one of Eric Dier or Jordan Henderson warming the bench come June 18th in Volgograd.
Both Dier and Henderson have captained the Three Lions, with the Tottenham star starting 12 of Southgate's 16 games in charge and Henderson nine, set to become ten when the Liverpool captain faces Costa Rica tomorrow.
RealSport examine England's options.
The role of the single pivot
Football's recent shift to 4-2-3-1 and 3-4-3 formations -amongst other variations- has seen a return to the double pivot midfield, with two central midfielders splitting offensive and defensive duties. A single pivot, however, takes on all responsibilities.
Particularly for England, therefore, the single pivot is tasked with protecting the defence through intelligent positioning to break up play with interceptions and tackles, as well as smart, incisive passing both forwards and laterally to not only keep possession ticking over as a 'safe option,' but create counter-attacking opportunities for the more advanced players.
The above screenshot is similar to how England lined up in the 2-1 win over Nigeria, resembling a 3-3-1-3 formation, though formations are fluid and shift throughout the game.
What won't change as the formation adapts to the run of play is the single pivot.
Whilst not as essential in the opening games against Tunisia and Panama -weaker opposition that England are expected to dominate in terms of possession-, a key tool for the single pivot is being able to protect the defence against counter-attacks.
This is where Dier excels.
Beginning his career as a centre back, the 24-year-old has defensive experience and understands what the role requires from a centre back's perspective.
For example, Dier was better positioned than Henderson to make tackles, resulting in more made per game (1.21) than Henderson (1.11). Dier made 41 in total, compared to Henderson's 30.
The Tottenham midfielder also made 20 more interceptions than Henderson, demonstrating a superior aptitude for breaking up opposition counters.
Concerning, however, is the fact that Dier made seven defensive errors last season, compared to none from Henderson, which perhaps denotes the Tottenham man's lack of concentration, making him a potential liability. Three central defenders could, though, negate this issue.
The argument, moreover, that Henderson made less defensive actions because of Liverpool's possession is flawed as Spurs, too, are a possession-orientated. In actual fact, Tottenham had a greater share of the ball (58.8%), on average in 2017/18, than Liverpool (58.0%).
Verdict: Eric Dier
The safe option
Crucial to the role of the single pivot in England's formation is their ability to pass. Henderson has forged a reputation for himself as one of Liverpool's best passers, rarely putting a foot out of place, becoming a key cog in Jurgen Klopp's ball-hogging machine.
A passing accuracy of 84% would certainly suggest as much, but Dier, again, is superior with an 86% passing accuracy, despite having made more passes overall (2078) than Henderson (1720). Fewer of Henderson's passes, moreover, went forwards (1115) than Dier's (1504).
In actual fact, Henderson, despite a contentious reputation amongst Liverpool fans as one of the league's best passers, didn't even feature in Liverpool's top ten most accurate passers. Dier, contrastingly, was sixth at Spurs, alongside Toby Alderweireld and Jan Vertonghen.
This is because Henderson typically played with Gini Wijnaldum and Alex Oxlade-Chamberlain -two ball-carrying midfielders- in front of him, so the best option was to lay it off simply for them to progress with. With Jesse Lingard the only central ball-carrying option, this isn't such an applicable strategy.
However, Henderson's passing is superior in one respect.
Playing with a pronounced split between attacking and defensive units puts a lot of pressure on the single pivot to link the two with their passing. This is something Henderson is very capable of, often the base of Liverpool's counter-attacking opportunities through his long passing.
Henderson's 5.6 long balls per game in the Premier League is a testament to as much. It's not to say Dier isn't capable of this, but he completed fewer per game (4.8) than his compatriot.
Despite making one fewer assist than Dier, Henderson did make more key passes (19), suggesting superior vision.
"Important figures for us..."
Southgate has already stated that he expects both Dier and Henderson to be "important figures" for the Three Lions over the course of the World Cup and there will be times where playing with a double pivot is essential, such as against stronger opposition like Belgium.
In truth, there's not much to separate the two midfielders. Both are good at a number of aspects, but none are exceptional at anything.
If anything, Dier's defensive superiority gives him the edge, given that's the essential function of the single pivot. Furthermore, his passing is hardly poor. He made more overall passes -13 of which were key-, had a better accuracy, assisted more goals and was dispossessed less frequently.
He also offers a goal threat from set pieces -an aerial presence that can be translated into defensive protection against lofted passes- and is tactically intelligent, denoted by Mauricio Pochettino's trust in him to cover multiple positions and roles.
Real jacks of all trades, but masters of none. Dier, though, is the slightly better jack.
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