This was India's fourth defeat in the last six Tests at home and in all four Tests -- including three against New Zealand -- their batters have flopped against spin.
Daryl Mitchell becomes only the second player from New Zealand to hold the top the ICC ranking for ODI batters.
Imam was in a hurry to reach his ton and, attacking the bowling, got an inside edge to Senuran Muthusamy's left-arm spin and was snagged at short leg by Tony de Zorzi's sharp catch.
South African stand-in captain Aiden Markram said home side Pakistan were well within their rights to prepare extreme turning wickets for their two-Test series, which starts in Lahore on Sunday, as they did last year to beat England.
South African captain Temba Bavuma on Sunday said his game is built around an unshakeable defence, which stood him in good stead on a disintegrating Eden Gardens track, where 38 wickets fell inside eight sessions.
Former players Irfan Pathan and Venkatesh Prasad have questioned the Indian team's muddled approach, lack of stability and the increasing reliance on all-rounders.
On a surface offering little assistance for bowlers, South Africa's top order had frittered away starts but number seven Muthusamy marshalled a lower-order surge with a composed 109.
Injury blow hit the South African camp as Anrich Nortje was ruled out of the second Test against West Indies.
The second and final Test starts in Guwahati from Saturday with India trailing 0-1 after the defeat on a challenging Eden Gardens pitch in Kolkata.
South African captain Temba Bavuma mixed grit with humour after his team's shock win over India in Kolkata, celebrating his hard-fought fifty and the "small hands" catch that turned the match on its head.
Spin great Harbhajan Singh said India don't have a specialist off-spinner for Test cricket.
Temba Bavuma discusses the no-handshake policy in India-Pakistan cricket, South Africa's T20 World Cup chances, and Indian batters' struggles against spin.
'Constant changes to the playing XI, batting orders, and frequent rotations prevent stability.'
Sack Gambhir before he damages any more careers, if you must. But it cannot stop there. The project ahead must be bigger, more ambitious, and far more urgent: Rebuilding the spine of Indian cricket from the grassroots up, and giving the Test team the seriousness it deserves. Only then will Indian cricket stop lurching from one crisis to another and begin, once again, to imagine greatness, suggests Prem Panicker.
'When you are playing on spin-friendly pitches, you need to prepare differently.'
Armed with a potent spin attack, taking on South Africa seems like competing against a "subcontinent team", Ten Doeschate said, admitting that they need to get better at negotiating the challenge posed by tweakers.
'You don't come to a country to win a Test match, you obviously want to win the series.
Quinton de Kock has reversed his retirement from ODI cricket and has been named in both the ODI and T20I squads for the Pakistan tour.
The Indian team management has not asked for a rank turner for the opening Test of the two-match series against South Africa beginning at the Eden Gardens on Friday, Cricket Association of Bengal president Sourav Ganguly said on Monday.
Countering Bumrah before spinners come into play will be key for SA: Graeme Smith
Shubman Gill might just want to be fit enough to bat, as even a half-fit skipper is seen as more effective than Sai Sudharsan, Abhimanyu Easwaran or Sarfaraz Khan.
Defending champions Sunrisers Eastern Cape registered their fourth successive victory with a 14-run win over Joburg Super Kings.
South Africa sharpen spin game in attacking net session ahead of Eden Test
On one of India's most challenging surfaces in recent memory -- a dry, unpredictable turning track where every ball felt like an event, Temba Bavuma played one of the defining innings of his career.
While the white-ball trophy cabinet kept getting heavier, Team India's fortunes in Test cricket swung wildly between hope and despair in 2025.
India, South Africa pretty close on bowling, batters will face big test in getting runs: Amla
The aura of home advantage -- long regarded as a hallmark of India's Test side -- seemed secure. But in barely over a year, that fortress has not just cracked, it has collapsed, raising uncomfortable questions about strategy, selection, and temperament.
'I definitely believe the kind of form he is in, the way he is batting, it will strengthen the Indian batting line-up.'
Bangladesh had been set a target of 274 for the win but resumed on the third morning on 11 for three and were bowled out inside 55 minutes.
The collapse, India's lowest failed chase at home, has left behind deeper fault lines than a dry Eden Gardens wicket can conceal.
K L Rahul on Saturday conceded that Indian batters' repeated struggles against spin, especially on home tracks, remain a concern.
Images from Day 1 of the first Test between India and South Africa, in Kolkata, on Friday.
Former South African cricketer Jonty Rhodes said that Team India does not need to prepare turning wickets as they can bowl out their opponents with their pace line-up and having another spin-friendly wicket for the second Test against South Africa will be a "big test of their ability".
Sunrisers Eastern Cape came up with a clinical performance with both bat and ball to register a 58-run bonus victory over Durban Super Giants in the SA20 match at Kingsmead.
Massive chance for series win in India, SA better-placed with spin resources: Bavuma
Sai Sudharsan and Prithvi Shaw failed to get big scores in their English county games for Surrey and Northamptonshire respectively.
The series promises a fascinating duel between the two modern-day pace greats.
IMAGES from Day 2 of the 2nd Test played between England and South Africa played in Old Trafford on Friday.
The first Test starts at Lord's on Wednesday.
Images from Day 1 of the third Test between Australia and South Africa at the SCG on Wednesday.
