Robert John Francis Hassell (born 4 June 1980) is an English former footballer who played for Mansfield Town, Barnsley and Bharat FC in I-League as a defender.

Barnsley boss Paul Hart brought Hassell to Oakwell as part of a rebuilding process in the summer of 2004, completing his move on 1 July.

Unlike two years' previously, he was on the winning side at the Millennium Stadium as Barnsley triumphed over Swansea City on penalties in the Play-Off Final.

He made multiple last ditch tackles and goal-line clearances whilst playing at right-back in a 2–1 win over Liverpool at Anfield, and was outstanding in an unfamiliar central midfield position as Chelsea were beaten 1–0 at Oakwell.

When Mark Robins was appointed Barnsley manager following the start of the 2009–10 season, Hassell initially dropped out of the team, yet soon found his way back in due to consistent performances and a high work rate.