Swansea City will progress to the the play-off final if they can avoid defeat to Brentford.
The Swans take on a strong Brentford side at Griffin Park on Wednesday with a one goal advantage following their first-leg victory on Sunday.
Forward Andre Ayew scored a stunning goal, after missing an earlier penalty, to give them a 1-0 win.
Brentford will feel aggrieved after full-back Rico Henry was sent off in the first match, receiving a straight red card which was later rescinded.
That result gives Steve Cooper's side a huge chance of reaching the play-off final.
Brentford had finished the Championship season three places and 11 points above Swansea in third position, narrowly missing out on automatic promotion to the Premier League.
Swansea had to produce a stunning performance at Reading and hope for a six-goal swing to snatch a last gasp play-off place.
The match will also be their last ever played at Griffin Park, with Brentford moving after 116 years at the stadium.
The home side will be full of confidence having already beaten The Swans 3-1 at the stadium earlier in the season.
The match kicks off at 7:45pm, with the winner due to play in the final at Wembley against either Fulham or Cardiff on August 4.
Cardiff will have to turn around a 2-0 home deficit to the Londoners, something that has never been done, if they are to make it an all Welsh affair.