In bowling, England have Jofra Archer fit and available along with veteran pace spearhead James Anderson, who is back in fray after workload management kept him away.
Leach is aware that with the pink ball, which tends to move around a lot more than the traditional red cherry, his role could change over the next few days.
Need to be extra cautious and focussed while batting during twilight: Rohit Sharma on pink ball Test
Rohit, who scored a dazzling 161 in the second Test in Chennai, had featured in the first day-night Test held in India against Bangladesh in November 2019 but did not bat during the twilight phase.
Pace spearhead Bumrah is bracing for a comeback after missing the second match at Chepauk and the seasoned Ishant Sharma was also seen in action.