Chahar "felt mild pain in his lower back" after the second ODI in Visakhapatnam on Wednesday, according to the BCCI. "The BCCI medical team examined him and has suggested that the fast bowler needs some rest in order to fully recover," a release said.
Chahar went wicketless for 44 runs in seven overs in the second ODI, which India won by 107 runs to level the series 1-1. In the first ODI, he finished with 1 for 48 from ten overs but West Indies chased down the target of 288 with ease.
Saini has played five T20Is so far and could make his ODI debut on Sunday unless India change their combination and don't field three quicks.