India wicket-keeper batter Sanju Samson revealed that the past three-four months have been mentally challenging for him but he kept at it by working on himself and bounced back by scoring his maiden ODI ton.

Samson was overlooked for the ODI World Cup in India with selectors preferring to go with the likes of Ishan Kishan and Suryakumar Yadav despite the Kerala batter averaging 55.7 with a strike rate of 104 in 13 ODI innings.

"The last three, four months were challenging for me mentally," Sanju said after the 78-run win on Thursday.

"So going through all that and coming here I think doing what I did today, I think I feel really happy and grateful." Samson was also not picked for the Asian Games, indicating that he is really low in the selectors' pecking order.

On Thursday, however, he took things in his own hand and scored his maiden ODI century to help India win the third game and clinch the series 2-1 against South Africa.

"I've been blessed in my genes. My father is also a sportsman, so how much ever setbacks you have, I think there's always no other way to come back and bounce back... think how much you can work on yourself and how you can come back more strongly," he added.

Elevated to the number three spot, Samson, who scored a measured 108, joined forces with Tilak Varma (52) to take India to a competitive target.

"Honestly, I think I was not looking at the scorecard. Until I had a partnership with Tilak till then I just wanted to play and like go with the merit. I just watched the ball and bat and the boundaries and the scoring options ultimately happened.

"So I was just focused on the process and playing one ball at a time and then I think the scorecard kept on ticking.

"When Tilak came in when we both had a tough four or five overs where I think (Keshav) Maharaj, was bowling the best. I think both the ends were a bit tight. That's when we thought that we need to go on and take some risks at the moment." Asked how he kept his calm during the knock, Samson said, "I don't know actually. It comes very naturally to me.

"It's very important to make really good decisions. When you are calm and when you are aware of your thoughts, emotions of your physical being and mental being that helps me to make some really good decisions." The home side looked on course for victory before the Indian pacers, led by left-armer Arshdeep Singh, bowled the South Africans out for 218 in 45.5 overs.

"I think the power-play, the way South African openers batted, I thought they are taking the game away five overs before.

"But after that when our fast bowlers came in between, and the ball I think was maintained nicely by all the teammates... the fast bowlers also hit some proper areas to get those crucial wickets of David (Miller) and crucial wickets were important for us."

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