Fast-bowler Khan suffered a hamstring strain during the first Test at Lord’s. The Indian cricket board later announced that the 32-year-old would be out for up to four months due to ankle surgery.
“It will be a big loss,” Anderson told Sky Sports News. “He's such a skilful bowler, especially in English conditions.
“It is a big loss for them but we can't get carried away with one individual going home because they've got strength in depth.”
The tourists face losing their number one ranking at Edgbaston when the teams face each other this week as England currently lead the series 2-0.