Adam Johnson has been found guilty of sexual activity with a child but cleared of another count of the same offence.
The jury at Bradford Crown Court had been deliberating since Tuesday lunchtime and returned with a verdict exactly a year after Johnson was arrested.
They cleared the 28-year-old England footballer of having oral sex with the 15-year-old but returned to give a majority 10-2 verdict finding Johnson guilty of the second count of sexual activity with a minor relating to digital penetration.
The judge told Johnson a custodial sentence was almost an inevitable outcome. He faces anything from four to 10 years in prison.
His father, Dave, sister Faye and ex-girlfriend Stacey Flounders were present for the verdict and watched from the public gallery as Johnson reportedly smiled as the "not guilty" finding was announced.
Johnson previously admitted grooming the girl and one count of sexual activity with a child on the first day of his trial.
But the former Sunderland FC winger denied two further charges of sexual activity with a child that were the subject of the jury's deliberations.
The charges arose from a meeting between Johnson and the girl in his Range Rover in County Durham in January last year.
Johnson admitted kissing the teenager but told the jury the encounter "went no further".
But she told the court he "put his hands down her pants" and she performed oral sex on him - a charge of which he has now been cleared.
The footballer was sacked by Sunderland in February, after pleading guilty to child sex offences.
Johnson will returned to court to be sentenced at a later date after Judge Jonathan Rose told him imprisonment was an "almost inevitable outcome".
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