The stumper batsman arrived in Dambulla on Monday morning as Sehwag pulled his right hamstring during the match against Pakistan on Saturday and is a doubtful starter.
"We flew in Karthik as a standby for Sehwag. But we will have to await the Asian Cricket council's clearance to play him in tomorrow's match against Sri Lanka," said Team India manager Ranjib Biswal.
If Sehwag is ruled out of the remainder of the Asia Cup, he will return home for treatment.
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