Jon-Paul McGovern gave Sheffield Wednesday the advantage over Brentford in their play-off semi-final first leg.
McGovern's early goal gave Wednesday a first-leg lead
McGovern rifled in a powerful shot from the right side of the area early on, after a good backheel by James Quinn.
McGovern hit the bar and the Owls' Paul Heckingbottom tested Stuart Nelson from a free-kick before the interval.
Glenn Whelan shot wide from distance and Quinn hooked a shot over the bar, while Chris Hargreaves blazed wide as the Bees battled for an equaliser.
Brentford substitute Isaiah Rankin was also lucky to escape with just a yellow card for a late tackle on Whelan as tempers threatened to boil over late on.
Sheffield Wednesday goalscorer Jon-Paul McGovern:
"It was a good performance from the boys, especially in the first half - the second half was a bit scrappy.
"However, I think it was always going to be like that when they're chasing a goal and playing it long, and we were trying to hold out.
"But it's only half-time, and there's another leg to go on Monday."
Brentford manager Martin Allen:
"It's only half-time. We go in at half-time 1-0 down, but all I do know is that we can play better.
"We didn't really get to grips with the game in the first 30 minutes, but that was perhaps to be expected.
"The atmosphere was unbelieveable here tonight, but at Griffin Park we will keep calm and we won't panic."
Sheff Wed: Lucas, Bullen, Heckingbottom, Wood, Bruce, Whelan, McGovern, Hamshaw, Rocastle (McMahon 79), Peacock (Talbot 77), Quinn (Brunt 90).
Subs Not Used: Adamson, Collins.
Goals: McGovern 12.
Brentford: Nelson, Turner, Frampton, Sodje, Gayle (Tabb 59), Talbot, Hutchinson (Rankin 64), Hargreaves, O'Connor, Burton, Pratley.
Subs Not Used: Bankole, Myers, Scott P Fitzgerald.
Booked: Hutchinson, Nelson, Rankin.
Ref: M Jones (Cheshire).