Manchester United are set to miss out on a £12 million transfer fee for Andreas Pereira, sources have told ESPN, with Brazilian club Flamengo preparing to abandon a deal to sign the midfielder at the end of his season-long loan spell.

Pereira, 26, moved to Flamengo last August with United giving the two-time Copa Libertadores winners an option to sign the Belgium-born Brazil international for a fee rising to £12m based on appearances.

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But despite making 34 appearances in all competitions for the Rio de Janeiro-based team, sources have told ESPN that Pereira has not done enough to convince Flamengo to complete a permanent move for the midfielder.

Having signed for United as a 15-year-old in 2011 after leaving the youth ranks of PSV Eindhoven, Pereira has struggled to realise his potential in the first-team at Old Trafford.

Loan moves to Spanish clubs Granada and Valencia, followed by another temporary move to Serie A with Lazio, have restricted Pereira to just 75 senior appearances for United.

Sources have said that Pereira moved to Flamengo in the hope of re-launching his career and was prepared to take a substantial pay-cut to seal a permanent move to the club.

But a costly mistake in the Copa Libertadores final defeat against Palmeiras last November, when a bad pass in extra-time gifted Flamengo's opponents a goal to claim a 2-1 win, has impacted on Pereira's performances and a return to Old Trafford is now the most likely outcome for the player, who still has a year to run on his United contract.

Sources have told ESPN that United are still hopeful that a deal can be done with Flamengo, who may yet be prepared to sign Pereira for a reduced fee.