It was the Brazilian's second of the game as Eddie Howe's men edged a five-goal thriller at the City Ground on Saturday evening, with Guimarães' well-worked opener having given them the lead.
Anthony Elanga equalised for the home side before Fabian Schär and Callum Hudson-Odoi exchanged goals just before half time to make it 2-2.
It was left to Guimarães to curl home what proved to be the winner in the final quarter of the contest, with the victory keeping United in touch with the Premier League's top six.
Serena Taylor was there to bring nufc.co.uk this gallery as the Magpies gained revenge for their Boxing Day defeat on Tyneside.