In his third match as captain, Warner scored 106 as Australia reached 5-199 to overhaul Sri Lanka’s modest tally of 195 with seven overs to spare in Pallekele on Sunday.
Warner, who endured a modest Test series and averaged just nine in the previous four ODIs, was uncharacteristically watchful for much of his 126-ball innings.
“It was a bit of a sigh of relief,” Warner said of his innings.
“I never doubt myself and I haven’t doubted myself and I kept backing my plan and executing my plans.”
The 29-year-old hit just one boundary in his first 59 balls, and was lucky to survive a scare when he appeared to be caught on 22 in the 13th over, with Australia languishing at 2-44.
“You do need a bit of luck in this game and I’m pretty sure I did hit that one to short leg tonight.
“But that’s part and parcel of this game. You get a bit of luck your way and fortunate enough tonight, I got that luck.”
With opener Aaron Finch not batting after injuring his index finger attempting to take a catch, Australia were struggling early in their innings at 2-25.
However, George Bailey continued his consistent form, compiling a patient 44 off 73 balls and sharing a partnership of 132 with Warner for the third wicket.
Bailey was named man of the series, with 270 runs at an average 67.5, strengthening calls for his return to the Test side for next year’s tour of India.
Bailey averages 60.9 in 18 ODIs played in Asia.
“He’s played fantastic, he’s played unbelievable cricket,” Warner said.
“He’s been a fantastic player in these conditions for a while now.”
Earlier all six Australian bowlers claimed a share of the spoils, with frontline paceman Mitchell Starc (3-40) once again in damaging form alongside spinners Adam Zampa (2-43) and Travis Head (2-22).
However Warner was unimpressed with his team’s effort after Danushka Gunathilaka (39) and Dhananjaya de Silva (34) put on an opening stand of 73 in 13.5 overs.
“I felt like we were playing grade cricket to be honest. The bowlers, they didn’t switch on in the first 10, they probably lacked a little energy and intent. They know that.
“But we still restricted them to 195 which is a fantastic effort on these wickets.”
Australia will complete their tour with Twenty20 matches against Sri Lanka on Tuesday and Friday.
Make your contribution to independent news
A donation of any size to InDaily goes directly to helping our journalists uncover the facts. South Australia needs more than one voice to guide it forward, and we’d truly appreciate your contribution. Please click below to donate to InDaily.