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Sheffield Wednesday boss Carlos Carvalhal is set to recall a number of players who were rested for the defeat at Wolves on Saturday.
Winger Ross Wallace is back after a three-match ban and striker Atdhe Nuhiu (knee) is fit to play.
Brighton will be without suspended duo Lewis Dunk and Dale Stephens, while veteran striker Bobby Zamora (hip) has been ruled out of both legs.
Steve Sidwell could replace Stephens, who starts a three-match ban.
After missing out on automatic promotion on the final day after drawing at Middlesbrough, Brighton travel to a sold-out Hillsborough to face a Wednesday side who finished sixth in the table, before hosting the return leg on Monday.
The South Yorkshire side are bidding to return to the Premier League for the first time since suffering relegation in 2000, while Brighton have not played in the top flight since 1982-83.
The Owls were successful in their only previous play-off campaign, winning the League One play-off final in 2004-05 by beating Hartlepool after extra-time.
Brighton have lost in the Championship play-off semi-finals twice in the past three seasons, first to rivals Crystal Palace in 2012-13 and then to Derby County in 2013-14.
The Seagulls lost a second-tier play-off final to Notts County in 1990-91 but were successful in their other play-off attempt, in the third tier in 2003-04 when they overcame Bristol City at the Millennium Stadium.
Both league meetings between Sheffield Wednesday and Brighton this season finished goalless.
Sheffield Wednesday boss Carlos Carvalhal:
“We cry, we smile and we have a lot of happiness with our fans through the season. The fans have followed us through the good and bad moments this season.
“I appeal to them to bring a positive vibe and they will see what the players will give to them.
“The team has shown all season that it likes big games. It can be a very good night for us.
“The fans have had a long time without reasons to smile or enjoy (the football). We can feel the positivity from them.
“We arrive here without pressure because we are the underdogs.”
Brighton manager Chris Hughton told BBC Sussex:
“You have to look at the game as two cup finals. One can affect the other.
“We are talking about three days between the two games, but we play in a league where we are used to playing on a Saturday and a midweek.
“When you get to a play-off I don’t think there are any favourites and it is a tough call between all four teams.
“That shows with the two results we have had against them this season. They are a very good side and certainly have goals in them.
“I expect it to be a tight affair. We know their dangers and that we can’t treat them lightly.”
The last three matches between Sheffield Wednesday and Brighton have ended 0-0.
Brighton have failed to score in their last five contests with the Owls; Keith Andrews in 2013 was the last Seagulls player to score in this fixture.
Six of the last 10 teams to finish third in the Championship have gone on to win the play-offs.
The Owls have lost just one of their last 20 league games at Hillsborough (W12 D7), conceding more than once on just two occasions.
The Seagulls are unbeaten in their last 14 matches, winning nine and drawing five.
No Championship player has scored more league goals in 2016 than Sheffield Wednesday’s Gary Hooper (11) and Brighton’s Tomer Hemed (11).