Dhawan (121 not out) played a solid knock and did not hesitate to take the charge to the bowlers when they bowled bad deliveries but the other batsmen adopted a very cautious approach as the hosts could only manage a runrate of 2.30 runs per over at the Jamia Millia Cricket Ground.
Rajat Bhatia (4 not out) was giving company to Dhawan when stumps were drawn.
The 19-year-old Dhawan, playing in only his third Ranji match, was confidence personified from the start as he played the Karnataka bowling attack with ease on the slow track.
He struck 10 fours and 2 sixes in his 246-ball knock and built a fruitful partnership of 103 runs in 52.3 overs with another rookie Avinash Bali (43) for the second wicket.
The stand was broken when medium pacer R Vinay Kumar rattled the woodwork of Bali, 11 overs before the scheduled close of play.
Veteran spinner Sunil Joshi then snared two quick wickets -- Mithun Manhas (11) and Sarandeep Singh (0) - in the penultimate over of the day to wrest back some initiative from the hosts.
Delhi 1st innings:
A Chopra c Uthappa b Joshi 15
S Dhawan batting 121
A Bali lbw b Vinay Kumar 43
M Manhas b Joshi 11
Sarandeep Singh c Shinde b Joshi 0
R Bhatia batting 4
Extras (b-3, lb-4, nb-4) 11
Total (for 4 wkts, 90 overs) 205
Fall of Wickets: 1-65, 2-168, 3-197, 4-197.
Bowling: D Ganesh 11-6-28-0; Vinay Kumar 11-3-24-1; N Aiyappa 13-1-36-0; S Joshi 34