Courtesy Sehwag's 105 and an equal contribution from Unmukt Chand (105), who scored his second successive century, Delhi declared their first innings at 425 for six.
In reply, Gujarat were 34 for one at stumps in the 13 overs that they faced in the day.
Sehwag curbed his natural instincts at times as he was focussed cashing in on a good run of form that he is in currently after his 64 against Rajasthan.
His best phase during four hour stay at the crease addition of 106 runs in just over 20 overs with Mithun Manhas (44, 62 balls, 8x4).
There were of course 14 boundaries and he reached his ton taking a single off left-arm spinner Pranjal Sutaria, who also dismissed him caught by Bhargav Merai.
"I believe Viru was never under any kind of pressure and is batting freely. If he played a game which is not his natural style, it shows his commitment for Delhi team. It was a type of century that the team expected from him," chief coach Vijay Dahiya said.
Delhi, however started the day on a sedate note with Unmukt really making rough weather of the three runs that he needed to score to complete his milestone.
He took more than 45 minutes to complete his sixth century before he went for a pull shot off a short ball from Kushang Patel to get out. Unmukt batted three minutes short of five hours and faced 227 balls, hitting 13 fours and four sixes in the process.
Gujarat 1st Innings: 34/1 (Shivam Sharma 1/12).
