The 26-year-old centre-back has been a long-term target for the Premier League champions, and could finally secure his much anticipated move to England with the impending arrival of Lisandro Ezequiel Lopez at Estadio da Luz.
David Moyes officially begins his Old Trafford tenure today, and will begin by overseeing the recruitment of Garay, who has enjoyed two successful seasons in Portugal after leaving Real Madrid in 2011.
The Spanish club retain a 50 per cent sell-on fee for Garay, and that is one reason why Befica are demanding £17million from Manchester United for the South American stopper's services.
With around £3.5million going towards the acquisition of Lopez, the Primeira Liga outfit stand to make around £1million profit from the €5.5million they paid Real Madrid for Garay two years ago.
Moyes is determined to strengthen his central defensive options despite inheriting a handful of options at Manchester United, and will be given the money to press ahead with capturing Garay.