Rice was already doubtful for Saturday's quarterfinal with a neural issue that affected his back and hamstring, but was struck by a bad stomach bug, exacerbating his ailments.
Despite his poor status, Rice was given the start against Norway before being taken off at halftime. Tuchel explained this move as a tactical substitution.
"We made a decision in half-time to become more offensive, to have a bit of an offensive shift," the German manager said following England's 2-1 extra-time win.
"I made the decision when we were 1-0 down and didn't want to go back on the decision because of the equaliser."
Tuchel said that Rice had done poorly in the days leading up to the Norway game.
"We had to take Elliot (Anderson) or Declan (Rice) off, knowing that Declan struggled after the last three days, when he was most of the time in bed. I knew he could not survive 90 minutes.
There was a possibility that it would go 120 minutes, so I didn't want to waste another change. The decision was to take Declan out earlier than he needed to go out, just to save us another change later down the match."
England take on Argentina on Wednesday, July 15th, at 21.00 CEST in the semifinals of the 2026 FIFA World Cup.
FIFA World Cup 2026
The 2026 World Cup is taking place from June 11th to July 19th in the United States, Canada and Mexico. The tournament features 48 national teams and is played at 16 modern stadiums.
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