Shardul believes there is still a "lot of cricket" left in him.
Thakur was part of India’s T20 World Cup squad in 2021 and also featured in the shortest format when Hardik Pandya was out of the team earlier this year.
However, Hardik’s return to the set-up after regaining bowling fitness has pushed Shardul back in the packing order.
"Of course, it's a big setback. Every player dreams to play in the World Cup, not just play but win it as well," Thakur said on the eve of the second ODI against South Africa.
"It's okay I'm not selected this time. But there's still a lot of cricket left and also there's the ODI World Cup next year. My focus will be to do well in whatever matches I play and make winning contributions," he added.
Deepak Chahar has been ruled out of the remainder of the ODI series against South Africa due to stiffness in his back. The right-arm seamer, who is one of the standbys for the upcoming T20 World Cup, now seems doubtful to travel to Australia for the marquee event.
"Injuries are part and parcel of the game, at some point, someone is going to get injured. We should not take it by heart honestly. There is a lot more cricket to come," Shardul said.
Asked if he fancies his chances, Thakur replied: "If injuries happen then anyone can come at any point of time. As of now, your responsibility is to be ready whenever and wherever you're asked to play. I will be mentally ready if I'm given a call-up. That's all in my hands."
Team India suffered a 9-run defeat at the hands of South Africa in the first ODI in Lucknow. Chasing 250 to win, the hosts were 51/4 but Sanju Samson (86* off 63 balls) and Shardul Thakur (33 off 31 balls) kept them in the hunt with a 93-run partnership for the sixth wicket.
"If you see teams who have done very well at international level, their batting line-up has been quite deep. Like Australia for instance, they have the likes of Pat Cummins, Mitch Starc coming at 8 or 9. Even for that matter England.
"I've been focusing on my batting for quite a long time now. obviously batting at no 7 or the one coming at no 9, if they can contribute it's always great. That gives you a cushion.
"We also can have our batting lineup deep and make the difference -- the difference of 15-20 runs that can be crucial in winning the match especially in white ball cricket," Shardul stated.
(With PTI inputs)