The stage was set at the London Stadium.
After an awful run of results that had seen the Hammers not win a game in their last 10, now was the chance for Nuno Espirito Santo - against the club who sacked him before he pitched up in East London - to earn three vital points and reel in the Tricky Trees and other clubs perilously close to the bottom three.
Win or bust
Already four points adrift at the start of play, this was simply a must-win game for the Irons. No ifs, no buts, no 'a point is better than nothing' narrative. A must-win.
The hosts could at least take heart in the manner in which they beat Nuno's Forest in August, winning 3-0 at The City Ground, though a 3-0 reverse to Wolves last time out - the Midlanders' first win of the Premier League season at the 20th time of asking for Rob Edwards' men - was much more telling in terms of current form.
Forest had also shipped three goals in their previous fixture, against Unai Emery's ever-improving Aston Villa side at Villa Park.
It probably wasn't the right fixture for Nuno to start tinkering with his lineup either, but four changes from the starting XI at Molineux meant he'd done just that.
Jean-Clair Todibo, Tomas Soucek, Taty Castellanos, and Lucas Paqueta replaced Callum Wilson - a scorer against Forest earlier in the season - Freddie Potts, Soungoutou Magassa, and Max Kilman.
Castellanos became the 341st player to play for the Hammers in the competition, with the only other side to use over 300 different players since the Premier League began being Chelsea (308).
So many personnel changes over the course of the EPL era are no doubt partly to blame for the Hammers' general lack of success in that time.
That West Ham captain Jarrod Bowen was making his 200th Premier League start for the club - becoming just the fourth player to reach that landmark after Mark Noble (373), Aaron Creswell (288) and Michail Antonio (220) - seemed to be overlooked by the importance of the fixture.
Though Morgan Gibbs-White's 127th Premier League appearance for Forest wasn't necessarily anything to write home about either in context, it meant he'd drawn level with Scot Gemmill, with only Steve Chettle (174), Mark Crossley (162) and Ian Woan (132) making more.
An eighth goal conceded from a corner for Forest
West Ham's new striker Castellanos was straight into the thick of it with the game's first shot in the second minute, earning a chorus of approval from home fans keen to see what type of forward they had in their midst.
A reasonably cagey opening from both sides produced a couple of half-chances, and Murillo's own goal for Forest in the 13th minute was in keeping with the nature of proceedings to that point.
That didn't bode well for visitors who had failed to win any of their last six league matches when conceding first; however, West Ham had failed to win any of their previous four league games in which they'd opened the scoring (D3 L1) - last doing so against Forest in August.
An eighth goal conceded from a corner was also only marginally better than West Ham's 11, the worst return in the English top flight.
A fifth goal for the Hammers this season in the first 15 minutes of league games is only bettered by Bournemouth (seven) in 2025/26, evidencing that Nuno's side have therefore proven to be fast starters, but clearly have been unable to build on their early momentum in matches.
Scarles can hold his head high
Both teams looked nervous in possession, with only Elliot Anderson taking responsibility in possession during those early stages.
The game ebbed and flowed, but, as might be expected from two teams that are struggling to put points on the board, there was little in the way of exciting goalmouth action.
Young Ollie Scarles could at least hold his head high in an insipid first half, with the academy graduate winning more duels (five) and making more tackles (three) than anyone else from either side.
Forest seize the initiative
Callum Hudson-Odoi hit the frame of the West Ham goal as half-time approached, the 10th time the East Londoners have been spared, with only Liverpool seeing the ball coming back off the woodwork more times in 25/26 (11).
Sean Dyche's half-time team talk had to be a good one given that, since returning to the Premier League in 2022/23, Forest were yet to win a game in which they'd trailed at the break (D9 L33).
They certainly began the half more purposefully, and their pass completion was far, far superior to West Ham's. Ola Aina led the way with 92.3%, with only Neco Williams (72.7%) and Omari Hutchinson (76.5%) of Forest's outfield players dropping below 80%.
By contrast, only Crysencio Summerville (91.7%), Matheus Fernandes (87.8%) and Castellanos (81.8%) made it above the 80% threshold.
That was always going to hurt the hosts, and it took just 10 minutes for Nicolas Dominguez to get the visitors back on terms, with his first goal since December 2023.
Forest seized the initiative in the game thereafter, limiting West Ham to just one shot from Bowen over the next 15 minutes.
A yellow card for dissent for Nuno highlighted his growing frustration, with the knowledge that, potentially, his job was at risk if his players didn't get the victory.
At least the hosts began to show some fight as the game entered the final stages, as they peppered Matz Sels' goal with efforts from a number of players, and had 68% possession during the 15-minute period directly after the 70-minute mark.
Areola's rash decision
Unfortunately, most shots were blocked or off target, and those that were on target didn't trouble the Forest custodian.
His opposite number, Alphonse Areola, would soon come to the fore himself with a rash decision which cost his side dearly.
Taking out Gibbs-White as he attempted to clear a cross only resulted in a penalty awarded to the visitors with five minutes left to play. A sixth penalty conceded this season in the Premier League is the most by any club, and a fourth conceded since 2022/23 by Areola puts him only behind Jose Sa (six) in that time.
A hush fell over the London Stadium as a sense of inevitability engulfed the home support. Sure enough, Gibbs-White stepped up and buried his spot-kick, with an immediate mass exodus from the stands being the result.
Those fans who stayed behind let their feelings be known, and West Ham's loss of 15 points from winning positions this season is a damning indictment of their current predicament.
Their last longer winless streak was from 23rd December 2006 to 4th March 2007, a run of 11 games, and Nuno won't want to equal that in his next match. If he's still the West Ham manager, that is.
