The 24-year-old scored for the third successive Premier League game after Jordi Amat’s clearance was deflected off Henderson and past Swans goalkeeper Lukasz Fabianski in the 58th minute.
Liverpool moved to within two points of fourth-placed Manchester United ahead of the visit of the Red Devils on Sunday.
Reds captain Gerrard was thrilled to make his comeback from a hamstring injury as a second-half substitute in the narrow win.
Gerrard wrote on Instagram: “Nice to be back out there with the team another big win well done lads #ynwa”
Gerrard added: “They all count mate @jhenderson applauding our fans after a nice win @martin37skrtel”
Liverpool striker Daniel Sturridge jokingly praised Henderson for a “great finish” after the England midfielder’s seventh Premier League goal of the season.
Sturridge posted: “Nice 3 points tonight… Great finish by Hendo. #Lfc #redordead #ynwa”
Finally, injured Liverpool left-back Jose Enrique issued an early Reds rallying cry ahead of the north-west derby at Anfield on Sunday.
Enrique wrote: “Great win by the team today. Another 3 points and united Sunday!!!! Let’s win this game!! Good night everyone”
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