The First Test in Hyderabad was Leach’s first competitive outing since suffering a stress fracture of the back last June, but the spinner hurt his knee while fielding on the opening day and then aggravated the issue on the second morning.
The 32-year-old bowled sparingly in India’s second innings and played no part in today’s training session in Vizag, where the series resumes on Friday.
There is a gap of more than a week between the Second and Third Tests and England are hopeful that their frontline spinner will be fit to return on the other side of it, but captain Ben Stokes confirmed he will be forced into at least one change this week as they look to build on a 1-0 series lead.
"He's ruled out of the second Test," Stokes said. "Unfortunately, the knock he took resulted in a haematoma in his leg. It's a big shame for us, a big shame for Jack, obviously after a long time out of the game with his back.
"To sustain that injury, first game back, obviously it's frustrating. But it's something we're assessing every day. The medical team have taken over that, and hopefully, it's not something that's too serious and keeps him out for longer in the series.”
Leach’s absence leaves Somerset teammates Shoaib Bashir in contention to make a Test debut, though England could also shift the balance of their attack by recalling James Anderson, having gone into the opener with Mark Wood as their sole seamer.
Bashir was late arriving in India earlier this month because of visa delays related to his Pakistani heritage and only arrived in Hyderabad just in time to watch fellow novice Tom Hartley bowl England to victory with seven wickets.
Bashir has even less of a county record behind him that Hartley, having played just six first-class matches in his career, but Stokes says he is ready to back the 20-year-old.
"If he was to play on this tour, then the great thing he has on his side is, what is there to lose?" Stokes said. "That is how I will be thinking about it, if he gets the chance to play: just to make sure I can give him the best experience I possibly can. Because you only play your first Test match once. If he does play, then I will be trying to make it as enjoyable and fun for him as I can.
"Myself, Baz [Brendon McCullum] and Popey [vice-captain Ollie Pope] will probably have a longer think about it. We looked at the wicket; I gave it a tap, and a play-around to make it look like I knew what I was doing. Bash is in the squad, we haven't brought him here to have an experience. If we feel we want to turn to him, we will."