The Brazilian international's well-crafted opener put Eddie Howe's side in front at the City Ground before Anthony Elanga levelled matters for the hosts.

Fabian Schär's half-volley restored Newcastle's lead before Forest hit back soon after through Callum Hudson-Odoi in first half stoppage time.

But Guimarães' second of the afternoon - expertly despatched from the edge of the box - won it for the Magpies with just under 25 minutes remaining, lifting Howe's men to within two points of a place in the Premier League's top six.

Forest's pace on the counter-attack looked like a trait that could cause United problems, and the hosts almost took the lead through one such break early on. Nuno Tavares' cutback was met by Morgan Gibbs-White, but his first-time shot flashed past the upright.

Former Newcastle goalkeeper Matz Sels was making his home debut for Forest after joining them in January and had to tip Sean Longstaff's drive round the post when the visitors began to settle into the contest, and on ten minutes the Belgian international stopper was beaten. It was a brilliantly-worked set piece, with a short corner allowing Kieran Trippier to whip in a deep cross to the unmarked Guimarães at the back post, and his volleyed finish with the outside of his right foot was crisp and clean.

Before Forest's leveller, there were warning signs that the speed of Elanga could hurt United, with the Swedish wideman racing beyond Dan Burn after being played in and forcing Martin Dúbravka to smother his attempt. But on 26 minutes, Elanga found space in between the Magpies' backline again, and ran onto Gibbs-White's pinpoint through ball to poke the equaliser beyond the onrushing Dúbravka.

Just before the break Howe's men moved back in front with a neatly-taken strike from Schär. Sven Botman's knock-down from a lofted Trippier free kick found the Swiss centre back, whose confident half-volley nestled in the bottom left-hand corner past Sels.

But they couldn't hold onto their advantage until half time, as Hudson-Odoi's deflected drive robbed them of their lead in the fifth minute of added time. The former Chelsea man took aim after a one-two with Nicolas Dominguez and his shot wrong-footed Dúbravka after cannoning off Lewis Miley on its way through a crowd on the edge of the box.

Nuno Espirito Santo's side began the second half with some urgency, and had the ball in the back of the net not long after the restart. Taiwo Awoniyi's finish from a tight angle was unerring but the big frontman had strayed offside in his eagerness to break clear of the Newcastle defence, with the goal chalked off.

Forest were firmly in the ascendency and Howe looked to change that by introducing Harvey Barnes, who netted on his return to action after coming off the bench in the Magpies' 4-4 draw with Luton Town last Saturday, but the hosts still carried a threat and were perhaps unfortunate to not have been awarded a penalty when Awoniyi tumbled as he looked to round Dúbravka.

But with a quarter of the contest remaining, Guimarães stepped up to provide the decisive moment. Tavares' pass was misplaced and Newcastle's primary string-puller intercepted it, lined up the shot and - with the help of Burn's clever block on a Forest player who had looked to charge down the effort - found the bottom corner with a curling strike that Sels couldn't keep out, sending the travelling supporters home happy after another absorbing encounter.