Cristian Arango struck a decisive winner and Denis Bouanga scored two as LAFC pulled off a thrilling 3-2 win over the LA Galaxy in their MLS Western Conference semifinal on Thursday night at Banc of California Stadium.

The teams traded first-half goals with Bouanga opening the scoring for LAFC and Samuel Grandsir netting an equalizer for the Galaxy before half-time.

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Bouanga looked to have scored the winner in the 80th minute, but Galaxy substitute Dejan Joveljic struck a sublime shot from outside the penalty area to eqaulize before Arango smashed into the top of the net in second-half stoppage time to seal the win.

LAFC will now face either FC Dallas or Austin FC, who play in the on Sunday night, in the Western Conference final on Oct. 30.

The Galaxy split the season series -- nicknamed El Trafico -- against rivals and Supporters' Shield winners LAFC and looked lively in the opening 20 minutes, with Riqui Puig having a penalty shout waved off and Douglas Costa hitting the crossbar from just outside the area.

LAFC sent a charge through the home crowd in the 23rd minute, though, when Carlos Vela picked out Bouanga with a pinpoint pass into the area and he shrugged off his defender beat Jonathan Bond to put LAFC in front.

The hosts looked set to take their lead into the break, but Galaxy winger Grandsir drew the match level before half-time with a well-struck volley from the top of the penalty area after a poor headed clearance from LAFC's Eddie Segura fell right to his feet.

A hard-fought, sloppy second half offered few clear-cut chances for either side until LAFC ratcheted up the tempo and took the lead when Bouanga got on the end of Ryan Hollingshead's low cross and tapped in at the far post to leave the Galaxy to chase the match in the final 10 minutes.

Greg Vanney's move to bring on Joveljic for Marky Delgado paid immediate dividends as the Serbian settled a pass from Victor Vazquez outside the box, slid to his right and curled a shot over the outstretched arms of Maxime Crepeau.

With the match seemingly headed to extra time, Bond spilled a volley in his direction following a corner kick into Arango's path and he pounced to finish from close range and secure victory for Steve Cherundolo's side.

Neither of LAFC's two high-profile additions this season featured in the match, with former Juventus defender Giorgio Chiellini an unused sub and Gareth Bale held out after picking up a leg injury during training this week.

The Galaxy have a 6-2-5 lead in the regular-season series, but have now lost on both occasions when facing LAFC in the playoffs including a 5-3 defeat in 2019.