Albion are level with Manchester United in the FA Cup semi-final at Wembley.
The Seagulls best chances included one that fell to Alexis Mac Allister who saw his feee kick beaten away by David De Gea.
Then a combination of Danny Welbeck and Kaoru Mitoma came agonisingly close to converting a Solly March cross.
Bruno Fernandes and Marcus Rashford have had the best efforts for United – Rob Sanchez saving well from Fernandes with his outstretched leg.