Warner and former Australia captain Smith only returned to global duty earlier this month after they both completed 12-month suspensions for their roles in a ball-tampering scandal in South Africa.
The duo's first match in England was a hastily arranged, unofficial warm-up match against the West Indies here on Wednesday.
Jofra Archer and Mark Wood, two of England's strike bowlers who can bowl consistently at 90mphr, sustained injuries and had to leave the field within few moments of their practice game against Australia in Southampton.
There were a few chants of "cheat, cheat, cheat" when Smith arrived, although a lone Australia fan shouted back "Get 'em Stevie!", according to BBC.
England are the favourites to win the World Cup on home soil and claim the trophy for the first time, having lost in the final three times - in 1979, 1987 and 1992.
"I'm pretty chilled, everyone's entitled to their opinion", Smith told Sky Sports during the innings break when asked about the crowd's taunts. "Fortunately, I was able to contribute today and hopefully I can take this form into the World Cup".More news: Aston Martin unveils James Bond-inspired vehicle
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Long a thorn in England's side, Smith went to 99 with a superb carved six over third man off Ben Stokes.
A patient half-century from James Vince (64) and Jos Buttler's blistering 52 from 31 balls put England in pole position in the chase but after the pair were dismissed with five overs of each other, the hosts faltered.
"There's been some good work for some of the bowlers", said Buttler.
Another four in Coulter-Nile's next took the stand-in England skipper to a 30-ball fifty but the Aussie seamer had his revenge next ball as he deceived Buttler with a slower ball and had him caught at midwicket.
While Wood walked off the field after suffering a hamstring injury in his fourth over, Archer also left soon after injuring himself while fielding at the deep.
Eoin Morgan made the same journey 24 hours earlier and was diagnosed with a small fracture in his left index finger, ruling the captain out of the 12-run loss, but he expects to be passed fit for the curtain-raiser against South Africa on Thursday.