The England international was in the right place to put Jordi Amat under pressure as the Swansea defender’s clearance deflected off Henderson and into the net past goalkeeper Lukasz Fabianski with 22 minutes remaining.
Liverpool moved to within two points of fourth-placed United ahead of their clash at Anfield next weekend, and Reds vice-captain Henderson is relishing the top-four battle.
“We can’t wait for Sunday. We’re high on confidence. United played well on Sunday,” Henderson told Sky Sports after the win.
“It will be a tough game, but we’re at Anfield, and we’re confident, so we hope we’ll get the result we need.”
Brendan Rodgers’ side struggled in the first half against Swansea, and Simon Mignolet was forced to produce a string of saves to deny Garry Monk’s men.
However, Liverpool were much-improved after half-time as Henderson scored his third goal in three Premier League games, and the midfielder paid tribute to Daniel Sturridge for creating the chance.
“It was a great pass from Daniel. It was a little bit fortunate, but you’ve got to be in the right positions to score,” Henderson added.
Liverpool are unbeaten in 13 Premier League games following a 3-0 defeat at Old Trafford in December.
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