The big frontman put the Seagulls one goal to the good from the penalty spot twenty-three minutes into his Brighton career.
Reading were not the only team this afternoon to feel aggrieved for having a spot kick awarded against them. Oldham reacted with fury when Mr E Ilderton said that Oldham's Paul Boshell had handled a Brighton cross.
Darius nestled the kick in the corner, sending Oldham keeper Les Pogliacomi the wrong way.
Henderson's strike partner Leon Knight, on loan from Chelsea, pounced to score the Seagulls other two goals as they went onto complete an easy 3-1 victory over Iain Dowie's financially instable side.
Brighton superstar Bobby Zamora, who was sold to Spurs during the summer, will soon be forgotten if his replacements continue to finish with such style.
After the game Brighton boss Steve Coppell was quick to praise his new strike partnership. He commented: "Darius and Leon are both quality players - I wish they were ours permanently. Darius adds a physical presence, which we sometimes lack and Leon was very lively.
"The result flattered us a bit because we weren't playing too well before the penalty, which probably knocked Oldham down slightly."
The Robins eventually lost 3-2 to Chris Turner's side, having fought back from 3-0 down. Igoe's snappy fifty-seventh minute free kick, which came on his Swindon debut, crept it's way past Tidman in the Wednesday goal.
Swindon, who harbour two other former Royals in Adi Viveash and Andy Guerney, will hope for a better performance in their Carling Cup First Round tie against Southend on Tuesday night.
Elsewhere, Phil Parkinson's Colchester United side went down by one goal to nil at Oakwell. Dean Gorre fired in a penalty for Barnsley two minutes after half time.
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