UPDATE 1-Cricket-India thrash South Africa by eight wickets in first ...

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JOHANNESBURG, Dec 17 (Reuters) - India's seamers Arshdeep Singh and Avesh Khan helped skittle South Africa out for 116 before Sai Sudharsan scored an unbeaten 55 on debut as India romped to an eight-wicket victory in the first One-Day International at The Wanderers on Sunday.

South Africa won the toss and elected to bat but the decision proved disastrous as they were bowled out for their lowest total on home soil in the 50-over format, narrowly underperforming the previous worst mark of 118 - also against India - in Pretoria in 2018.

Singh picked up five wickets for 37 runs in his 10 overs and Khan took 4-27 in eight as they bowled a wicket-to-wicket line that had seven of the South African batters either bowled or dismissed leg before wicket.

All-rounder Andile Phehlukwayo offered some resistance for the hosts with 33 from 49 balls before he became Singh’s fifth and final victim.

"The plan was to keep it simple," Singh said after his first ODI in more than a year. "I hadn’t opened my account in One-Day Internationals having played three games before this, so to get a five-for is really special.

"The wicket was helping, so we tried to maintain the basics and use the right lengths.

"Before the game we thought there wouldn’t be much movement, so we were surprised, but there was a nice breeze and some purchase off the wicket, so the plan was to hit the wickets and look for lbws."

Khan removed the middle and lower order for his career-best bowling figures in ODIs.

India were positive in their chase and reached their target in 16.4 overs with exactly 200 balls to spare.

Debutant left-handed opener Sudharsan scored an elegant 55 not out in 43 balls, including nine fours.

He was supported by Shreyas Iyer, who was caught with victory in sight having scored 52 from 45 balls.

The second game in the three-match series will be played in Gqeberha on Tuesday.

Both teams are missing several of their regular players, who are either injured or rested for the two-match Test series that follows. (Reporting by Nick Said; Editing by Hugh Lawson)