Manager David Moyes hopes West Ham United's FA Cup win at Brentford will be a turning point in their season.
Said Benrahma knocked out his former club as he collected the ball after a perfectly timed Declan Rice tackle and thumped home from 25 yards.
That gave the Hammers, who are fourth-bottom in the Premier League, their first win in seven games.
"I think the result in midweek [2-2 at Leeds] and a good win here today is something to build on," said Moyes.
"Getting through in any cup competition is important and we just about got there today.