Railwaymen score three late goals to defeat Bees in opening league encounter.Brad Inman scored twice as Crewe opened their Under-21 Professional Development League Two defence with a 4-2 win over Jon De Souza's side.
The winger opened the scoring in the third minute but The Bees hit back with goals from Josh Clarke and Jermaine Udumaga to lead 2-1 with 15 minutes to go.
Inman grabbed his second from close range before two goals in the final three minutes settled the game for the home side as George Cooper and Callum Saunders found the net.
Brentford's starting XI included Adam Forshaw as he continued his recovery from injury while Montell Moore and Jack Bonham, unused substitutes in Tuesday's night First-Team win over Blackpool, also started.
It couldn't have been a worse start for Brentford as Joe Maloney played a square ball across the edge of his penalty area which Inman intercepted and rolled past Bonham from 12 yards.
The home side quickly set about trying to increase their advantage and Bonham was the busiest man on the pitch.
The former Watford man turned away another effort from Inman before making a great save with his legs to deny Saunders as he raced through unchallenged.
Crewe were rampant and there was nothing that Bonham could do as Cooper cut inside a thundered a shot against the bar from 25 yards.
Bonham denied Saunders and Inman either side of a Cooper effort which flashed just wide of The Bees' goal before Brentford finally registered a shot on target in the 25th minute as Forshaw's long-range effort was held by Scott Shearer.
The home side were getting much of their joy releasing their front three in behind Brentford's high backline and that nearly led to their second as Chris Atkinson played in Inman but Cooper's shot from his cutback was brilliantly parried away by Bonham.
A smart corner routine nearly drew The Bees level but Jake Reeves' volley from 25 yards fizzed a yard over the bar while Emmanuel Oyeleke saw a shot deflected wide from 12 yards as The Bees started to get into the game just ahead of the interval.
Forshaw forced a regulation save from Shearer before Jon De Souza's side did draw level with the last kick of the half when Clarke latched onto Charlie Adams' perfectly weighted through ball and lifted a shot over Shearer and high into the Crewe net.
The Bees scarcely deserved the equaliser but the boost it gave them was evident in the opening stages of the second-half as it became a much more even contest.
Reeves and Moore both fired wide while at the other end James Jones shot straight at Bonham and Saunders couldn't quite connect with Liam Nolan's scuffed cross.
Forshaw shot wide of the target twice in quick succession but his replacement on the hour Udumaga made no mistake when presented with The Bees next opportunity as he seized on a defensive lapse to roll home under Shearer.
Having taken the lead Brentford set about trying to secure the win as Shearer saved from Reeves and Tyrell Miller-Rodney before excellent work from Clarke presented Reeves with another chance 12 yards out but he delayed and his eventual effort was blocked behind.
Crewe had been largely on the back foot in the second-half but they grabbed an equaliser with 13 minutes to go as Inman was given time to take the ball down inside the box and fire, with the aid of a deflection, low past Bonham.
The home side had already seen Saunders and Jones denied by Bonham before they thought they had gone in front with eight minutes to go but a late linesman's flag for offside saved The Bees as Saunders headed home at the back post.
However they did eventually re-take the lead as some overplaying in the Brentford backline presented the ball to Cooper who curled home past Bonham from 18 yards.
James Collins's side made sure of the three points in injury time as more poor defending allowed Saunders the time to round Bonham and roll home to condemn Brentford to an opening day defeat.
Crewe Alexandra DS: Scott Shearer; Perry Ng, Jon Guthrie, Toby Mullarkey, Matt Neal; George Cooper, Liam Nolan, Chris Atkinson, Brad Inman; Callum Saunders, James Jones.
Subs not used: Liam Matthews, Joe Howell, Callum Pritchard Ellis, Andre Brown, Chris Speed
Goals: Brad Inman 3, 77; George Cooper 88; Callum Saunders 90
Brentford: Jack Bonham; Lionel Stone, Daniel O'Shaughnessy, Raphael Calvet, Joe Maloney (sub Gradi Milenge 63 mins); Jake Reeves, Adam Forshaw (sub Jermaine Udumaga 63 mins), Emmanuel Oyeleke; Josh Clarke, Charlie Adams; Montell Moore (sub Tyrell Miller-Rodney 63 mins)
Subs not used: Mark Smith
Booked: Lionel Stone 50
Goals: Josh Clarke 45+1; Jermaine Udumaga 67.