Saina and Carolina have the chance to grab the number one world ranking spot from China's dominance when they compete in the $275,000 India Open starting at the Siri Fort Sports Complex from Tuesday.
The Chinese have ruled the badminton world number one spot since 2010 and if either or the two manage the accomplishment of taking top spot it would be an historic first for both India or Spain as no woman from either country has ever achieved this distinction.
Both tasted success early in the season as Saina won the Syed Modi Grand Prix Gold title defeating the Spaniard in the finals in Lucknow.
Carolina avenged the loss beating the Indian at the All England final.
If both reach the final, Saina's No.1 status will be assured.
BWF Secretary General, Thomas Lund confirmed the change in the ranking should both players progress.
"This is certainly a most intriguing situation and it underlines the wealth of talent coming through in women's singles in the past season.
"We have a range of very good players who are vying for titles and who are motivated to be the No.1 player in the world. It's a big achievement for any player and this competitiveness is great for our sport."
Saina has failed to clinch the India Open since the event collaborated with the World Superseries circuit in 2011.