Two specialist batters, B Sai Sudharsan and Devdutt Padikkal, are available, along with seam-bowling allrounder Nitish Kumar Reddy, who rejoins the squad after being rested for the first Test.
In its official statement, the BCCI revealed that Gill has been responding positively to treatment and has been cleared to travel.
In addition to discussing the pitch, Gambhir updated on the condition of captain Shubman Gill, who had left the field with a neck injury during India's second innings.
The loss adds pressure on India, who have now suffered three defeats in the current WTC cycle, including two earlier in England.
South Africa stun India by 30 runs in a dramatic Kolkata Test as Harmer and Maharaj seal a historic win. India lose first home Test at Eden Gardens in 13 years.
From domestic nearly-man to master craftsman, Harmer's long, winding journey meets its defining moment at Eden Gardens
The highest successful run chase at the Eden Gardens dates back more than 20 years, when India chased down 117 against South Africa in 2004
BCCI confirmed the development minutes before the start of day three, ending all hopes of Gill returning to rescue his team on a wicket that has only grown more treacherous with time.
Hours after leaving the field, Gill was seen being stretchered into an ambulance, wearing a cervical collar to lock his neck in place.
India take 7 wickets before stumps with SA leading the tie by 63 runs in the match which could see a result on Day 3 of the Test.
Concern for India as Shubman Gill walks off with apparent neck injury after brief but attacking start
Sehwag had held the mark with 90 sixes, but Pant has now moved past him with 92 - and counting
A major boost for India came in the form of Rishabh Pant's comeback from a foot injury that kept him out of action for three Tests.
Bumrah's figures of 5/27 make him the first fast bowler since Ishant Sharma in 2019 to claim a five-wicket haul on the opening day of a Test in India.
Washington Sundar set to bat at No. 3 batting position in the India vs South Africa first Test. A detailed look at his Test and first-class stats, top-order credentials and evolving batting role.
Young captain Shubman Gill will rely on experienced campaigners like Jasprit Bumrah and Mohammed Siraj, while Rishabh Pant is set to return after a lengthy injury layoff.
South Africa entered the opening Test without their premier fast bowler, Kagiso Rabada, who was sidelined due to a rib injury.
India have received a major boost with Rishabh Pant returning from the foot injury that sidelined him for three Tests.
Under the new leadership of Shubman Gill, the hosts aim to continue their impressive home record, especially after bouncing back strongly from a 2-2 draw in ENG and the rare 3-0 loss to NZ last year.
Eden Gardens, historically known for its batting-friendly surfaces that occasionally offer assistance to spinners, may play differently this time.