Sehwag smashed 42 off 32 balls, while the left-handed captain Gambhir scored a 40-ball 41, helping Delhi complete the chase of 134 with 10 deliveries to spare at the Punjab Cricket Association stadium.
Sehwag hit five fours and a six, and Gambhir found the fence six times, the knocks doing their confidence a world of good.
Chasing a modest target, Delhi were off to a flier as both Sehwag and Gambhir tore apart the Himachal bowling attack with consummate ease.
With their two experienced campaigners looking in good touch from the word go, the target proved too small for Delhi, and barring left-arm spinner Bipul Sharma (2-28), none of the Himachal bowlers could pose any sort of challenge whatsoever.
The two put on 82 runs for the opening wicket in 11.1 overs before Sehwag was sent back by Gurvinder Singh.
Gambhir followed 13 runs later, falling to Aksahy Chauhan to leave
Delhi at 95 for two.
Unmukt Chand and Mithun Manhas fell in quick succession, leaving it on Rajat Bhatia (13) and Milind Kumar (22) to complete the task.
Earlier, Delhi won the toss and opted to bowl, a decision that seemed to have paid off as Himachal were struggling at 10 for two in the second over itself.
After being reduced to 41 for three at one stage, skipper Paras Dogra (40 not out off 41 balls) steadied the ship and, in the company of Nikhil Gangta (29) took Himachal to a modest total against their formidable opponents.
Rishi Dhawan (27) played a cameo towards the end to give Himachal the much-needed thrust, which though was not enough in the end.
For Delhi, pacer Ishant Sharma was the pick of the bowlers, returning figures of 2-22.
Services thrash J&K
Chandigarh: Pacer Shadab Nazar claimed four wickets as Services thrashed Jammu and Kashmir by seven wickets in another North Zone T20 match at the Sector 16 Stadium.
Opting to bat, the J&K batsmen put up a paltry 91 runs in 18.4 overs before Services overhauled the target with 20 balls to spare.
Samiullah Beig (24) was the highest run-scorer for J&K, while skipper Parvez Rasool (5) also failed to inspire his side.
Nazar drew first blood for Services when he trapped Adil Reshi (13) in front of the wicket. Arshad Kawaja (1) was Nazar's second victim.
Nazar went on to pick two more wickets, including that of Samiullah to end J&K innings inside 20 overs.
Left-arm spinners Abhishek Sakuja (2-14) and Avishek Sinha (2-23) bagged two wickets each, while pacer Suraj Yadav claimed 1 for 18.
Chasing the target, Rajat Paliwal scored an unbeaten 29 and added 45 runs with Anshul Gupta (25) for third wicket to take the side home after openers Nakul Verma (19) and Yashpal Singh (17) were dismissed by medium pacer Abid Nabi (2-13).
Paliwal hit four boundaries in his 27-ball knock and Gupta's 25 came off 26 deliveries and was laced with a four and a six.
Shukla steers Bengal past Assam
Kolkata: Skipper Laxmi Ratan Shukla struck an unbeaten 53 to set up former champions Bengal's 44-run win over Assam in an East Zone league match at the Eden Gardens.
Shukla slammed seven fours in his 50-ball innings and Arnab Nandi's cameo of 28 not out from nine balls was studded with nine boundaries and one six. The pair added 38 runs from 15 balls, propping Bengal's total to 161-4 after they were put in to bat.
Requiring more than eight runs an over, Assam failed to put up any fight after Shukla gave the breakthrough in Rishav Das (18) as the young and experienced off-spin duo of Aamir Gani (3-18) and Saurashish Lahiri (2-22) shared five wickets between them to seal an easy victory.
Pacer Ashok Dinda (2-29) grabbed two in the last over to bundle out Assam for 117 in 20 overs.
Odisha beat Tripura by six wickets
Kolkata: Odisha put up an all-round show to post a comfortable six-wicket win over Tripura in a low-scoring affair in the East Zone league match at the JU second campus ground in Salt Lake.
Odisha off-spinner Jayanta Behera claimed three for 22, including two in two balls, while pacer Basanta Mohanty (2-17) got rid of the tail to bundle out Tripura for a mere 116 in 19.5 overs after they were put in to bat.
In reply, opener Paresh Patel (43 from 37 balls; 4x2, 2x6) gave Odisha a flying start as he along with Natraj Behera (23) put up 44 runs for the opening wicket before Govind Podder (17 not out) sealed the chase with an over to spare.
Image: Virender Sehwag
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