BTW, Indian selectors still seems to be confused about whom to select as replacement for Pant and Iyer. They can pick either Suryakumar Yadav or Shubman Gill, and keep KL Rahul on the other end. Or they can pick both of them, and then drop Rahul. In that case, Rohit Sharma will open the batting along with Shubman Gill. KS Bharat is included in the squad, but I will be surprised if he makes his debut and considered ahead of Ishan Kishan. Among the bowlers, only Ashwin and Shami are confirmed. Selectors may go with Axar for the first match.
KL Rahul and Gill seem more like fixed in the playing XI but IMO confusion would be about who should play at the opening slot and Number 5. KL Rahul is not in good touch but i would still prefer him over SKY.
Nathan has an impressive record in tests he has already taken 436 wickets in 115 matches. In India, he has taken 34 wickets in just 7 matches. In my opinion, he is a big threat to Indian batters. Steve Smith has been good against Indian bowlers. Out of 6 test matches played in India, he has scored 660 runs which includes 3 centuries and a half-century.
Nathon Lyon is good but not that threatening in India, sure he'll take at least 1 fifer here n there but largely Indian batters shouldn't face many difficulties facing him. He averages 30 on a rank turner, which is not a good stat for any spinner.