Forest's manager headed towards the tunnel with a puzzled expression, gaze fixed on the ground. Following 7 games in charge with no victories, his prospects looked as unclear as a fog on the Tyne.
While the home side were far from their ferocious form, second-half goals from the Brazilian midfielder and Nick WoltemadeâWoltemade's a spot-kickâultimately secured them a restorative another Premier League victory of the season.
From the start, the manager's padded jacket wrapped him similar to a duvet, but the Australian's agitated gestures indicated it offered no solace.
No coat could protect Postecoglou from the fear that his victory-less beginning at Forestâtaking over as the first manager in 100 years to go winless in his first half-dozen fixturesâwould continue before a possible dismissal over the upcoming pause.
And yet, his side performed reasonably well during a tight at the back first half.
Although Elliot Anderson on occasion outshone even Sandro Tonali in midfield, showing everyone why the Newcastle boss was so hesitant to let go of the homegrown talent, the defender marked the striker out of the game, and Nicolò Savona caused the full-back difficulties down the home left.
In fairness to the forward, who received little service to his feet or head, his side's attacking play lacked fluidity.
True, it took a superb stop from Matt Selsâex- Magpies shot-stopperâto keep out Joelinton effort, and the player failed to convert a couple other chances, but overall, Forest's defending was much improved.
Given it is only a month since Postecoglou replaced Nuno EspĂrito Santo and matches have come in quick succession, with precious little time to implement his ideas on the training ground, all the talk of an looming dismissal seemed somewhat premature.
Or at least it did until GuimarĂŁes lifted a effort past Sels and into the top corner from the edge of the area.
That saw Postecoglou shaking his head in clear despair, wearing the anguished expression of a man who had just lost his house keys.
The Forest squad protested about a possible foul on their playmaker by GuimarĂŁes in the buildup, but their appeals were ignored by the referee.
With the Italian now ascendant in midfield, Anderson was not the only away player struggling to make an impact.
At this point, the coach had removed his anorak and pushed up the arms of his jumper. With Forest seldom looking likely of scoring and Newcastle threatening to shred their earlier improved backline, he was clearly under pressure.
It took another excellent stop from the goalkeeper to deny Tonali's driven cross-shot, before the resultant set-piece prefaced Woltemade's shot crashing the bottom of the crossbar.
Sels then made an superb two quick stops from the defender and the winger before finally being beaten again from the penalty spot by the German.
That spot-kick was given when the midfielder's poorly timed challenge sent GuimarĂŁes tumbling down.
Stepping up, the German forward to confound Sels by lifting a rather audacious spot-kick into the top left corner.
That marked Woltemade's 4th strike for the club since his seventy-million-pound transfer from the German side in August, making a mockery of comments from senior figures at Bayern Munich that Newcastle were âidiotsâ to pay so heavily for the striker.
This may not have been his finest performance in Newcastle colors, but his skill to retain possession and use his sticky control to connect attacks is already well on the way to a cult hero on in Newcastle.
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