Meghalaya chose to bat and could only muster 89 for 8 in their allotted 20 overs, thanks to double digits from Larry Sangma (34) and Yogesh Tiwari (22).
Vijaykumar Vyshak was the bowlers’ choice for Karnataka, registering figures of 3 for 5 from his four overs.
In pursuit of the modest total, Devdutt Padikkal perished in the fourth ball for a duck.
But Agarwal and Pandey teamed up to score match-winning 90 runs for the comfortable win.
In another Group C match, Kerala defeated Haryana by three wickets.
Kerala chose to field and limited Haryana to 131 for 7 and then chased the target in 19 overs with three wickets in hand.
Elsewhere in the group, Services crushed Arunachal Pradesh by nine wickets, while Maharashtra defeated Jammu and Kashmir by three wickets.
Meghalaya 89 for 8 in 20 overs (Larry Sangma 34, Yogesh Tiwari 22; Vijaykumar Vyshak 3/5) vs Karnataka 90 for 1 in 10.1 overs (Mayank Agarwal 47 not out, Manish Pandey 42; Abhishek Kumar 1/15).
Arunachal Pradesh 75 all out in 19.4 overs (Nabam Tempol 29; Parth Rekhade 2/10) vs Services 76 for 19 overs (Anshul Gupta 38 not out, Rahul Singh 33 not out; Tanmay Gupta 1/20).
Jammu and Kashmir 175 for 5 in 20 overs (Abdul Samad 55, Shubham Khajuria 44; Rajvardhan Hangargekar 2/28) vs Maharashtra 176 for 7 in 19.3 overs (Rahul Tripathi 59, Paavan Shah 51; Umran Malik 4/27).