BBC Sport - Newcastle United full-back Tino Livramento has been ruled out of England's World Cup campaign with a calf injury and has been replaced by Chelsea defender Trevoh Chalobah.
Livramento, 23, sustained the injury during a training session on Sunday before England's World Cup opener against Croatia on Wednesday night (21:00 BST).
Livramento's involvement in the tournament had already been in doubt after he missed the final five weeks of the season with a thigh injury.
Chalobah, who has one cap, will not join up with the squad until after the Croatia match.
He is on his way to England's camp in Kansas City as the rest of the squad head to Dallas.
Outfield players who sustain a serious injury or illness can be replaced in a World Cup squad up to 24 hours before the team's first match of the tournament gets under way.
Livramento, who was handed his international debut under Gareth Southgate in November 2024, has featured five times during Tuchel's reign, starting twice.
He came on at half-time during England's 1-0 warm-up win over New Zealand but was left on the bench against Costa Rica.
Reece James is Tuchel's first choice at right-back but there are also question marks about his fitness, following another injury-plagued campaign.
The 26-year-old missed nine games for Chelsea at the end of the season because of a hamstring injury.
Other options who are already in the England squad include Djed Spence and Ezri Konsa.
Spence, who can play on both flanks, has featured six times under Tuchel while Konsa, predominantly a centre-back, has played 11 times, including nine starts.
Chalobah has not featured for England since June 2025 when he played the full 90 minutes in a friendly against Senegal, but was on the bench for multiple World Cup qualifiers under Tuchel.
Like Konsa, the 26-year-old's preferred position is centre-back.