A collective bowling effort and fifties from R Samarth and KL Rahul underlined Karnataka's dominance over Assam in Indore. The defending champions stretched their lead to 404 runs at stumps on the third day.

Resuming from an overnight 58 for 3, Gokul Sharma and KB Arun Karthik pushed their fourth-wicket partnership to 62 runs before the latter fell to Shreyas Gopal

Tarjinder Singh gave Gokul good support and grafted 30 off 80 balls to keep Karnataka at bay for 61 more runs. However, Vinay Kumar struck twice in the 68th over, first trapping Tarjinder lbw and bowling Gokul for 58.

A collapse ensued as Assam lost their last four wickets for 16 runs and folded for 185. Shreyas and S Aravind collected three wickets each, while Abhimanyu Mithun and Vinay picked up two apiece.

Buoyed by a first-innings lead of 262, the Karnataka openers Samarth and Rahul shared a partnership worth 124. Rahul struck 11 fours and a six, scoring at close to run-a-ball. The stand, though, ended in the 30th over when left-arm spinner Syed Mohammad dismissed Rahul for 73. Three overs later, Manish Pandey was bowled by seamer Krishna Das for a nine-ball duck, but Samarth and Robin Uthappa, stayed unbeaten on 54 and 6.

Uthappa dropped down to No.4 as he was tired after keeping wicket. "CM Gautam was injured and Robin kept, so I asked him to bat at four. Robin was tired, I didn't want him to open and his wicket is crucial to us. Also, Samarth is an opening batsman himself," said Karnataka batting coach J Arunkumar

Gautam, who pulled a muscle while keeping, left the field on precautionary grounds, but is expected to bat tomorrow.