‘You've not done enough to convince that manager’ - Roy Keane tells Maguire and others
The centre-back was a high-profile omission from the final 26-man squad, a decision that has sparked considerable debate.
While Maguire was reportedly part of the provisional 55-man list, manager Thomas Tuchel ultimately selected Dan Burn and Jarell Quansah as defensive options ahead of him.
Other notable players left out of the World Cup team included Phil Foden, Cole Palmer, and Morgan Gibbs-White.
What Keane said
Keane has insisted that any player who fails to make the cut must take personal responsibility. Speaking before England's friendly match against New Zealand, the former midfielder offered his typically forthright opinion.
"Every time we do an England game, we speak a lot about players who have been left out or in terms of the squad are left out of the starting XI," Keane said.
"But I think if you can't get into a squad of 26, that's on you. That is on the player, you've not done enough to convince that manager."
"There will always be uproar with England for players that are left out if they play for certain clubs, but that's on you. If you can't make a squad of 26, that's on you, don't blame anyone else."
England is set to begin its World Cup campaign against Croatia in nine days, with Ghana and Panama also in their group.
The team started their preparation with a 1-0 win over New Zealand, and their final preparation match will be a friendly against Costa Rica.