Axar is currently in South Africa, where he is playing for India 'A' in the tri-nation tournament.
While Axar would be joining the Indian team in Sri Lanka, off-spinner Jayant Yadav is expected to stay back as cover.
During Sri Lanka's second innings, Jadeja fielded a ball off his own bowling and threw it at batsman Malinda Pushpakumara "in a dangerous manner", according to the on-field umpires.
The 23-year-old Patel, like Jadeja a left-arm spinner, has played 30 one-day internationals and must beat left-arm wrist-spinner Kuldeep Yadav to the second spinner's place to make his Test debut in the dead rubber.
Jadeja is currently the top ranked test bowler as well as top test all-rounder but Ravichandran Ashwin remains India's spin spearhead.
"Since Axar will be finishing his one day engagements by Tuesday evening, he can join the team by Thursday (August 10). It was a toss up between Axar and Jayant but Axar is a like for like replacement in absence of Jadeja. In any case he (Axar) will be a cover as Kuldeep will be playing," a BCCI official said on Tuesday.
Jayant was selected for the South Africa 'A' tour but currently is in India as he recently lost his father Jai Singh. He is expected to be given time to recover from the personal tragedy.
"If one looks at how the selectors have gone about their job, the four premier Test spinners during home series were Ravichandran Ashwin, Jadeja, Jayant and Kuldeep. Kuldeep is ahead in pecking order," the official added.
Meanwhile, senior left-hander Suresh Raina will be appearing for a fitness test at the National Cricket Academy in Bengaluru.
"After months of hard work it's time for an evaluation. Off to NCA! Looking forward," tweeted Raina.
Raina's appearance for a fitness test keeps him in contention for a place in the Sri Lanka bound ODI and T20I squad along with A team skipper Manish Pandey, who has had a fabulous tri-series in South Africa.
Yuvraj Singh and Rishabh Pant could be axed from the limited overs squad.
Raina was among the five standbys for the ICC Champions Trophy.
Image: Axar Patel celebrates a wicket.
Photograph: BCCI
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