"It was a good start, I am happy. I was able to get used to the court and the atmosphere. It has been a long time, coming back after three years, it's a very special one. 2016 (Olympics) was different and 2020 (2021) was completely different. It is a sort of mixture of both," said Sindhu about her Olympic journey.
"I am enjoying and looking to the second match."
After a couple of unforced errors, Sindhu was quick to assess the condition and took control of the proceedings, racing to a 11-4 lead.
The world No 111 Fathimath was no match against the former world champion who finished the first game in a mere 13 minutes.
The second game followed a similar manner with Sindhu claiming the first four points in the blink of an eye to take an early lead.
However, Razzaq capitalised on Sindhu's error to bridge the gap to make it 3-4. But it became a one-sided contest once again as the Indian increased the gap to 10-3.
In the end, Sindhu had as many as 14 match points but the world No 13 needed only one to seal the tie.
The 10th seeded Indian, who won the silver medal in the Rio Games in 2016 and a bronze in the last edition in Tokyo, will take on World No 75 Kristin Kuuba of Estonia in her second group match on Wednesday.
Sindhu has been mentored by the legendary Prakash Padukone in the past few months, and she said the association has been beneficial to her.
"I have been with Prakash sir for more than six months now and it's going on very well. Everything is coming together. We have to know each other very well to work together," she said.
"Prakash sir is a legend, he is very experienced and he will come and tell me what is required, what I need to change."
Asked about the aspects of her game which has improved since she started working with Padukone, she said, "Overall, it has not changed the way I feel but there have been add-ons.
"When after I got injured It was getting difficult to move well on court and it was at times getting hard to get the momentum back. We worked on that, we worked on strokes, not just on net and defence but on overall game. You need to be at your 100 per cent in every big tournament or on every stroke."
She said mental strength is very important for players, especially during a big event like the Olympics.
"It is very important to be mentally strong. You at times don't know what is happening, everything gone from you. we worked on the mental things also. I tried to be positive, keep myself calm and do yoga."