Sindhu defeated Japan's Nozomi Okuhara 21-19, 21-10 in the semi-finals on Thursday.
The 21-year-old Indian will now face world number one Carolina Marin of Spain on Friday (August 19) in the title clash. Marin beat China's Li Xuerui 21-14, 21-16 in the 1st semi-final. (Reactions from Twitter after Sindhu's win)
Before today, no Indian player had reached the final at Olympics badminton. The final will be played at Riocentro Pavilion.
Sindhu, after a hard-fought first game, had it easy in the second set (from 10-10, she won 11 points in a row to seal the match) to storm into the gold medal match.
World number 10 Sindhu is the 5th Indian woman in Olympic history to win a medal. She is assured of silver now. Karnam Malleswari, Mary Kom, Saina Nehwal, Sakshi Malik were the previous female medal winners for India.
Sindhu, however, is the first Indian woman to get a silver or gold. All past winners had settled for bronze. If the Hyderabad girl wins gold on Friday, she will be only the second individual gold winner for India after shooter Abhinav Bindra (2008 Beijing).
Bindra was quick to tweet, saying he wanted Sindhu to join him in the gold club where he is feeling lonely. "What a player !! @Pvsindhu1 I'm waiting for you to join me in the club. You have no idea how lonely it's been !!!," Bindra wrote.
When is the final?
Sindhu Vs Marin gold medal match is on Friday (August 19) at 6.55 PM IST (Rescheduled from 7.30 PM IST)
Where to watch on TV?
Star Sports network will LIVE telecast this match. LIVE streaming on Hotstar
Here are the details of previous meetings between Sindhu and Marin. The Spanish player leads 4-3
18 November 2015 (Hong Kong Open)
Marin won 21-17, 21-9
17 October 2015 (Denmark Open)
Sindhu won 21-15, 18-21, 21-17
24 January 2015 (Syed Modi International Championships)
Marin won 21-13, 21-13
30 August 2014 (BWF World Championships)
Marin won 21-17, 21-15
27 June 2014 (Australian Open)
Marin won 21-17, 21-17
2011 (Maldives International Challenge)
Sindhu won 21-7, 15-21, 21-13
24 April 2010 (World Junior Championships)
Sindhu won 21-17, 21-19