If Karthik's 151 laid the winning base for the hosts as they posted a mammoth 422 for nine declared in their first innings, then medium-pacer Krishna's five-wicket hauls in both the innings respectively sounded the death knell for Rajasthan.
Getting behind a 236-run trail in the second innings, the Ashok Maneria-led Rajasthan was shot out for 84 on the fourth and final day as pace-spearhead Arup Das and Krishan bagged five wickets apiece.
Brief Scores:
Assam: 422/9 declared in 151 overs (K B Arun Karthik 151, Swarupam Purkayastha 50; K Ajay Singh 5-116).
Rajasthan: 186 and 84 all out 28.4 overs (Ashok Menaria 20 batting; Arup Das 5-39, Krishna Das 5-23).
Points: Assam 7, Rajasthan 0.