are reportedly keeping tabs on Brazil Under 20 striker Walter.
The £5million-rated 19-year-old caught the eye of United's scouts at the South American youth championships last month, according to the Daily Mirror.
Sportsmail understands the Barclays Premier League champions primarily had their eye on Gremio playmaker Douglas Costa at the tournament in Venezuela.
But Internacional striker Walter was more impressive, finishing thetournament as joint top scorer with five as Brazil won the competition.
Barcelona and Juventus are also said to be interested in Walter, but Internacional recently played down speculation.
VIDEO: Watch Walter in action.
The Brazilian club's president Vitorio Piffero said: 'He was a bigsuccess in the Under 20 championship, but there has been no offer.
'Every now and then, people want to sound things out but this hasn't happened. And it's not our intention to sell him now.'
Fellow target: Gremio attacking midfielder Douglas Costa
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