After being swept 4-0 in the preceding T20 series, India looked transformed with the return of senior stars Virat Kohli, Rohit Sharma and Jasprit Bumrah. Gill anchored the chase with 80 before retiring hurt with cramp, while Axar followed his four-wicket haul with an unbeaten 57 as India reached their target of 259 with 28 balls to spare. Washington Sundar finished unbeaten on 52 and sealed victory with a six.
India lost both openers cheaply, with Rohit out for 11 and Kohli trapped lbw by Jofra Archer for five, but Gill shared a crucial 101-run stand with Shreyas Iyer before leaving the field.
England briefly threatened a comeback when Harry Brook's direct hit ran out Iyer for 35 and ODI debutant Josh Tongue dismissed KL Rahul, reducing India from 149-2 to 160-4. Axar and Sundar then combined in an unbroken century partnership to guide India home.
Axar's unbeaten fifty completed an excellent all-round display after he took 4-62 with the ball. Bumrah, returning after missing the T20 series, claimed one wicket but produced a probing spell that exposed England's top order.
England's innings collapsed after a promising start. Ben Duckett and Jacob Bethell added 61 before the hosts lost three wickets in six deliveries to fall to 64-3. Bethell made 14, Duckett 43 and Brook edged Bumrah to Rohit Sharma at slip for one.
Jos Buttler, playing his 200th ODI, scored five before Sam Curran fell for a duck, leaving England 80-5. Will Jacks made 20 before Joe Root and Liam Dawson revived the innings.
Root, dropped on seven, finished unbeaten on 76 while Dawson struck 68 from 83 balls in a seventh-wicket stand of 121 that rescued England from 107-6. Axar returned to dismiss Dawson before cleaning up the tail as England were bowled out for 258.
The defeat was England's 14th in 20 ODIs despite January's series win in Sri Lanka and marked a disappointing start to Brendon McCullum's tenure as full-time white-ball coach following his removal from the Test role.
Gill later said he expected to be fit for Thursday's second ODI in Cardiff after confirming he had only suffered cramp. The series concludes at Lord's on Sunday.
Andy Flower has ruled out the possibility of replacing Brendon McCullum and becoming England's next Test coach, insisting he is happy with the work he is doing in T20 franchise leagues.
Former India cricketers Mohammad Kaif and Zaheer Khan have shared assessments of Gautam Gambhir's spell as India's head coach, with both agreeing that stronger communication is essential.
Jonathan Trott, who has been linked with the England Test coaching job, will join the Ireland staff as a consultant ahead of their ODI series against Afghanistan next month.
Brendon McCullum admits his results as head coach of England's Test side were not good enough and it was probably for the best that he was relieved of his duties in the longest format.
