Compliments mean little to West Ham at this stage of the season. They hit the woodwork three times, had a goal ruled out for a tight offside and contributed to an entertaining game against strong opposition but none of that mattered when full time arrived and Nuno Espírito Santo faced up to his side missing a huge opportunity to take a big step towards winning their fight against relegation.

It remains too tight to call. This defeat keeps West Ham two points above the bottom three and means they will drop into the relegation zone if 18th-placed Tottenham beat Aston Villa on Sunday night.

The frustration gnawed at West Ham. They could have heaped pressure on Tottenham but were undermined by frailties in both boxes and Brentford took full advantage, moving into sixth place and boosting their hopes of qualifying for Europe thanks to a messy own goal from Konstantinos Mavropanos, Igor Thiago scoring for the 22nd time in the league this season and Mikkel Damsgaard rounding off the scoring with a clever shot.

While Keith Andrews celebrated his impressive side ending a seven-game winless run, West Ham’s thoughts turned to whether they can respond against Arsenal next week. This setback will test their character. At the start of this game they looked too determined to make their fans sweat. They were bright going forward, Pablo the first to threaten when his hustle forced an error from Sepp van den Berg, but they were too open without the ball and could have conceded a hatful during a breathless first half.

Brentford’s first chance came inside the first minute, Dango Ouattara whistling a shot just wide, and they soon led. Keane Lewis-Potter delivered a deep cross from the left, Crysencio Summerville’s failure to track his runner left Mads Hermansen exposed and Michael Kayode capitalised on the opening. His presence forced Summerville to prod against a post, then caused a stretching Mavropanos to push the ball into the back of the net when it bounced across the line.

Nuno must have fumed at Summerville switching off. West Ham looked unprepared for Brentford’s aerial power. The back four creaked and further chances arrived, Damsgaard spurning the best of them when he shot wide of an empty net after a howler from Hermansen.

Brentford could have been out of sight by half-time, with Lewis-Potter and Van den Berg also failing to convert presentable opportunities. Then again, West Ham had plenty of moments at the other end. Mavropanos had an equaliser ruled out for a marginal offside and Jarrod Bowen finished tamely when well placed, while Taty Castellanos saw two efforts come back off the woodwork and another draw a leaping save from Caoimhín Kelleher.

West Ham were competing but lacked ruthlessness. The second half began with Castellanos crossing for Pablo, who headed over. There was a clumsiness to West Ham in both boxes. Brentford pushed and led 2-0 when Thiago converted a penalty awarded when a brilliant twisting run from Ouattara lured El Hadji Malick Diouf into bringing the winger down with a desperate tackle.

Letting in such a soft goal rattled West Ham. Ouattara almost made it 3-0, flashing another shot wide. The visitors grew ragged as they committed players forward and they began to lose their composure, Castellanos fortunate not to see red for a heavy challenge on Lewis-Potter.

Sensing that Castellanos’s head had gone, Nuno replaced the striker with Callum Wilson. West Ham mustered late defiance, Summerville hitting the bar, but perhaps they should have known there was no way back. Brentford, after all, have won only three of their last 16 London derbies. The problem for Nuno is all those victories came against West Ham.

Brentford were always in control during the second half. They kept West Ham at arm’s length and clinched the win when Damsgaard nutmegged Mateus Fernandes with a shot that rolled past Hermansen.