Bumrah is slated to return in national colours during India's tour of New Zealand in January-February 2020.
The pacer is recovering from a stress fracture on his lower back.
India did make a rousing start to their journey in day-night Test as they dismantled Bangladesh.
India lost that match by just 4 runs after New Zealand posted a mammoth 212 runs.
"I genuinely believed that I could hit a six."
"He discussed where I was going wrong."
Karthik faced flak from all quarters for his refusal to take the run.
Krunal Pandya was another spinner to move up in the rankings.
The all-rounder's performances in testing conditions must have impressed the team-management.
Talking about how he can contribute to the side, Shankar said he wants to keep himself flexible.