Tottenham Hotspur midfielder must perform against Croatia and/or Spain, or risking losing his place to Nathaniel Chalobah.
Dier may have scored the winner for Spurs against Cardiff City in the Premier League on Saturday, but his form in 2018/19 has been poor so far.
The former Sporting CP star has begun the season slowly, showing signs of sloppiness in possession.
He has also proven totally ineffectual in some of Tottenham’s games.
It’s a similar story at international level too, with Dier not really standing out in Russia for England.
He plays a very specific and important role, but he hasn’t been fulfilling it with the same conviction as a couple of seasons ago.
Dier’s Three Lions place is under threat
With Gareth Southgate having shown that he isn’t afraid to make big calls regarding his squad selections, Dier really has to start performing in an England shirt.
He may well get the chance against Croatia, which is the first of the Three Lions’ two matches.
Obviously Croatia made the 2018 World Cup final and have a plethora of great offensive players.
Dier will therefore need a big performance against the likes of Luka Modric and Ivan Rakitic.
Knocking on the door is Nat Chalobah, who is back in the international setup after fracturing his kneecap.
The Watford man is raring to make his mark for the seniors after making 97 appearances at various youth levels.
Clearly Southgate rates him after picking him at the earliest available opportunity.
If Dier fares poorly across the two games, then he could lose his place indefinitely, but only, of course, if Chalobah himself can make it count.