Ivan Toney and Josh Dasilva scored the goals as Brentford recorded a 2-0 victory over West Ham United at London Stadium in the Premier League on Friday night.
Toney made the breakthrough in the 18th minute of the contest before turning provider for Dasilva, with Thomas Frank's side moving into ninth spot in the table courtesy of their fifth league success of the campaign.
The result has seen West Ham, who have now lost their last five Premier League matches, drop into 17th position, just one point outside of the relegation zone, with the Hammers picking up just 14 points during a poor first half of the season.
David Moyes's side came close to making the breakthrough in the fifth minute of the contest when Declan Rice, having collected a pass from Lucas Paqueta, struck one towards the bottom corner, but the England international's 25-yard effort smashed against the outside of the post.
The Hammers had another opportunity in the 12th minute when Craig Dawson climbed highest inside the box to meet a corner from Jarrod Bowen, but his header was wide of David Raya's goal.
Against the run of play, Brentford managed to take the lead in the 18th minute of the contest when Toney tapped home from close range after West Ham goalkeeper Lukasz Fabianski had kept out an attempt from Christian Norgaard.
The home side had a half-chance to level in the 28th minute when Vladimir Coufal found Gianluca Scamacca with a deep cross, but the Italian's header was straight into the arms of Raya.
Brentford's goalkeeper then had to keep out a powerful drive from Emerson Palmieri in the 34th minute before Angelo Ogbonna headed wide from an Aaron Cresswell cross less than one minute later.
The Bees doubled their advantage in the 43rd minute, though, with Dasilva racing onto a flick from Toney, outpacing Cresswell in the process, before picking out the bottom corner with a clever finish.
Paqueta missed the far post with a 20-yard strike just before the interval, with the Hammers entering the half-time break two goals behind.
West Ham were given a penalty in the 47th minute of the match when Ben Mee brought Bowen to the ground, but a free kick was eventually awarded following a VAR review, and Bowen's effort came to nothing.
Bowen was the player carrying the fight to Brentford, with the Englishman bringing a smart save from Raya just before the hour, before Dawson tried his luck from distance seven minutes later.
Brentford almost had a third in the 71st minute when Saman Ghoddos collected a deflected free kick from Toney, but Fabianski was on hand to make a smart save, before Toney hooked over from the resulting corner.
Scamacca had two efforts for West Ham in the 77th minute, first stinging the palms of Raya before firing over the crossbar from outside the box.
Raya then kept out a header from Dawson, but there was to be no late response from the Hammers, with the pressure increasing on Moyes following another Premier League defeat.
Brentford's night ended on a sour note, though, as Toney had to be stretched off the field in second-half stoppage time with what appeared to be a serious knee injury.
Next up for West Ham is a trip to Leeds United on January 4, while Brentford's first match of 2023 will see them welcome Liverpool on January 2.
