The Scotland international, who has bagged four goals since moving to Hillsborough last summer, is a big doubt for tomorrow’s trip to third-placed Reading.
Carvalhal said: “Fletcher has been playing and training these last few weeks with some limitations. He is not 100 per cent. He is a very good professional, that’s why he has been involved, to try and help the team.
“We decided this week, to give him special treatments, and he was not involved in training.”
Carvalhal expects Fletcher to train today and will also assess Ross Wallace (back/hamstring), Glenn Loovens (dead leg) and Kieran Lee (hip) before finalising his squad.
“We will see what reaction he has,” said Carvalhal. “We took this decision to try and get him near 100 per cent in the future, rather than train and play with limitations.”
It would be a big blow for Wednesday if Fletcher is unavailable for selection, with strikers Fernando Forestieri and Gary Hooper already ruled out. To plug the gap, Carvalhal could turn to Atdhe Nuhiu, who claimed a hat-trick in a behind-closed-doors match at Notts County in midweek.
Highly-rated youngster George Hirst may also come into Carvalhal’s thoughts. The 17-year-old has been scoring on a consistent basis for the Under-18s and the development squad.
“Usually on the bench we have two defenders, two midfielders, and two attackers,” said Carvalhal. “George is training with us this week, and is one player who would be available if we need him.”