His first notable victory was in 2004, when he won the Under-9 State Chess Championship, receiving a silver medal. The following year, he participated in the 13th Asian Schools Chess Championship and attained fourth place. In 2007, he won the Under-11 State Chess Championship.
Girish had another significant victory in 2015 when he won the Combined National Junior Chess Championship. Following this, he captured the State Senior Championship in 2017.
In the same year, he also won the National Under-25 Chess Championship, which earned him his first grandmaster norm. He received his second grandmaster norm at the 2018 Aeroflot Open, and achieved his final GM norm at the Pardubice Open held in Czech Republic in 2018. He was awarded the Grandmaster title the following year.