Herath split his finger during his team's match against England and the wound is expected to take 7-10 days to heal, Sri Lanka Cricket (SLC) announced today.
Herath, who injured himself while attempting to take a return chance off Jos Buttler in the 49th over of England's innings on Sunday, required four stitches on his spinning finger.
The injury has put Herath in doubt for Sri Lanka's next match against Australia, to be held on March 8, but he is yet to be ruled out.
This will be the second replacement in the Sri Lanka squad. Earlier, the opening batsman Upul Tharanga had replaced Jeewan Mendis.
The 29-year-old Prasanna has played 22 ODIs and was a member of the Sri Lanka ODI squad in New Zealand in January.