The Hull captain timed his move to perfection to power home a cross from Ahmed Elmohamady in the 37th minute. The win moved Hull four points clear of the relegation zone with four games to play.
The loss is a further blow to Liverpool's hoping of qualifying for the Champions League for a second successive season.
Liverpool is seven points behind Manchester United, which is fourth in the final qualification spot for Europe's elite competition.
Hull, Swansea win to lift survival hopes, Boro sink deeper
