Just exactly what does Lewis Dunk have to do to convince Gareth Southgate that he warrants a place in the England squad?
Dunk, who has one England cap to his name, has been impressive for eighth place Brighton this campaign but has been overlooked for each of the England squads so far this season.
The likes of Tyrone Mings and Michael Keane have made the cut for Southgate but Dunk's exclusion continues to mystify many at the Amex Stadium.
Keane was dropped for this latest squad with Mings, Harry Maguire, John Stones, Joe Gomez and Fikayo Tomori the recognised centre halves.
Dunk's statistics this season stack up well. Under Albion head coach Graham Potter, Brighton build their attacks from the back, with most stemming from either Dunk or midfielder Dale Stephens.
The Albion skipper is comfortable at the fulcrum of a defensive trio but can easily adapt to a conventional back four.
He has played every minute of every Premier League match this campaign (990 minutes) and has the seventh highest pass completion rate in the League with 725 - the highest of any England centre back. Trent Alexander-Arnold (737) is the only Englishman with more passes this season
Dunk also has the highest number of interceptions among all English defenders with 25 and has made an impressive 37 clearances. He is ranked third overall in last man tackles won and he has not made a single error this season that has directly led to a goal.
His two assists were both defence splitting passes that teed-up Neal Maupay at Watford and then Aaron Connolly against Tottenham.
So where's the problem?
My hunch is that Southgate believes he's too similar to Maguire...and if Maguire is fit, Southgate's made it clear he gets in ahead of everyone else.
Mings I feel has been included ahead of Dunk as he's also a fine defender but crucially he is the only left-footed centre back in the squad. It gives Southgate the option to go three at the back if needed, with Mings able to play comfortably on the left side of the defensive trio.
Stones is a class act when fully fit and it's likely he and Maguire are the first choice pairing when England are at full strength.The excellent and lightning quick Gomez, aged 22, and Tomori, aged 21, are gaining experience but both have proved capable at that level when called upon - Southgate sees them as the future.
It's tough on Dunk. At 27 he's at the peak of his powers and yet too old to get in ahead Gomez and Tomori. He's too similar to displace Southgate's favourite Maguire and just too right-footed to oust Mings.
Dunk has been magnificent for Albion so far this season and he should have been included in the previous squad ahead of Keane.
The Everton man was dropped for this latest international call-up but the return of Stones - who at just 25 already has a wealth of international and Champions League experience - keeps Dunk on the sidelines.
All Dunk can do now is show at Old Trafford, against the likes of Marcus Rashford and Anthony Martial, that he deserves to be in the debate.