The Manchester Evening News is reporting that the Red Devils are set to get one over their bitter rivals for the second time in 2018.
The same article states that the 16-year-old defender had a trail at the 20-time English champions back in August.
According to MEN, Bejger will be included in Manchester United’s academy intake for the 2018-19 season after his successful trial.
Manchester United scout Piotr Sadowski is credited with unearthing Bejger, who captained Poland’s Under-16 team to victory over Moldova last week.
The Red Devils beat Manchester City to the signing of Chile international Alexis Sanchez in the January transfer window.
The 20-time English champions are still 16 points adrift of the runaway Premier League leaders following a mixed second season under Mourinho.
Manchester United could still win some silverware this season but the Red Devils will have to beat Tottenham Hotspur in the FA Cup semi-final.
The Red Devils lost 2-1 to La Liga outfit Sevilla in the Champions League round of 16.
Manchester United are in second place in the Premier League table and two points ahead of Liverpool FC.
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