Tendulkar, who won the ICC Cricketer of the Year award last year, currently shares the number-one spot with Jacques Kallis of South Africa.
However, the 38-year-old Indian batsman opting to take rest means losing one per cent of his ratings points for every Test he misses, giving Kallis the sole number one position.
Tendulkar could potentially drop behind England's Jonathan Trott, who though is still in the qualification period for batsmen, is likely to move further up the ladder depending on how he performs in the remainder of the third Test against Sri Lanka in Southampton.
Like Tendulkar, other missing Indian players Virender Sehwag, Gautam Gambhir and Zaheer Khan will not only drop points but might also slip in rankings.
In the ICC Test Championship table, India leads the West Indies by 42 ratings points. As the rankings system is weighted to reflect this difference, anything less than 3-0 whitewash will see India drop points.
India will stay at 128 ratings points only if it wins the series 3-0 but will slip to 127 if it wins 2-0 while it will drop to 126 ratings points if it wins 1-0 or 2-1.
India will drop six ratings points if West Indies wins the series 1-0 or 2-1 and seven points in case of a 2-0 win for the West Indies.
A series win by West Indies will not only mean the gap between the top two ranked Test sides will be narrowed, but it will put the Caribbeans ahead of Pakistan in sixth position for the first time since the ratings were introduced in June 2003.