A 50-run partnership for the third wicket between Kamlesh Diva (51) and Bimal Jadeja (49) enabled Saurashtra notch up 185 for seven in the stipulated 40 overs with Subank and Sanje Dobe taking two wickets apiece.
Chasing the formidable total, Delhi veterans added 42 runs for the third wicket by Amir Singh (46) and Suresh Kohli (35) as the match shifted to a thrilling mode at the closing stages.
Anil Rana hit a breezy unbeaten 24 off 19 balls to guide Delhi to victory in the last over with four balls to spare.
Delhi skipper Amir Singh was named Man of the Match while Shankar Saini, also from Delhi, was named Man of the Series.
Brief Scores: Saurashtra 185 for 7 (Kamlesh Diva 51, Bimal Jadeja 49, Kasyap Mehta 30) lost to Delhi 186 or 8 in 49.2 overs (Amir Singh 46, Suesh Kohli 35 Anil Rana 24 no).