David Raya makes a good save to protect Brentford's two-goal aggregate lead, getting a strong hand to Connor Roberts' strike from the Swans right, tipping it over the bar.

In to the final half an hour then, and Brentford appear to have control of this tie.

Swansea need to find a dramatic comeback from somewhere.

Just imagine the noise around Griffin Park now, if fans were allowed in... Their final ever game at this tightly-enclosed old ground, 3-0 up and just over half an hour away from reaching Wembley. It'd be bouncing.

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Brentford's free-kick after that yellow card is a dangerous one but, inside the box, Ethan Pinnock heads off target. The marking was fairly slack, once again.

Swans substitute Ben Cabango can't keep up with the raw pace of Ollie Watkins and slides in late on the Bees striker. It's a yellow.

Dafydd Pritchard
BBC Sport Wales

To remind you, away goals are not a factor in the play-offs, so Swansea now need two goals to force extra time.

Nick Bruzon: Oh my word. Rico. What a gem of a cross. What a finish from Mbeumo. Red card justice delivered . And how .3-1

The goal came less than a minute in to the second half, just after the Swans had made a double change.

The Welsh side have a mountain to climb now.

Brentford, in their traditional red and white kit, get this game going again. It could be the final 45 minutes of football at Griffin Park, unless Swansea can force extra time.

Swansea make two changes at the break. Mike van der Hoorn and Jay Fulton aren't coming back out.

Yan Dhanda and Ben Cabango come on instead.

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Dave Head: Been to Griffin Park twice as a Spurs fan. Nov 92 was my first live game, Brentford 2 Spurs 4, Chris Hughton played for Brentford. Second time was a pre season friendly in Aug 93, when Jason Dozzell made his Spurs debut. 0-0 bore draw. Great atmosphere for both games

Richard Harrison: I used to live in Ealing and often visited Griffin Park. Great pubs and I remember chatting to Tony Robinson at half time v Bristol City

rich mitch: Brentford v Exeter C in our halcyon days. Travelled up and our mate bought the famous balti pie. During warm up Grecians player missed the goal.. Whack... hit the pie straight out of his hand. He never did get the full Griffin Park experience!

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Throughout the day, BBC Sport readers have been voting for your players and manager of the year in our awards and you can see the results here.

Andrew Sanders: Two terrific fully committed teams going at each other hammer and tongs. Fabulous!

David Thackeray: Whoever wins the play-off final will have played 51 games. A bit of a run in one or both of the cups and you could be looking at 55/56 games. Personally I think it's too much, but I'd be interested in other people's views. BTW this is a good game.

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There ends what was, ultimately, a superb first half for Brentford. They turned things around in the tie with two goals inside the first 15 minutes.

Can Swansea respond after the break?

Andre Ayew is up on his feet again and looks set to continue, as we edge towards half-time.

We're in to two minutes of added time at the end of this first half but there'll be a bit more than that, because Swansea's Andre Ayew is down receiving some treatment, after colliding with Pontus Jansson.

Ollie Watkins has worked incredibly hard for the hosts in this first half. I want to know what he had for breakfast.

Brentford are winless in their past 11 EFL play-off games, losing eight of those and last winning in 2002 against Huddersfield in the third tier semi-final second leg.

That looks set to change tonight, after a big first half.