Indeed, it is the club's second successive father-son captaincy rein as hooker Richie Sweeney led the Blues this past season, following in the footsteps of his own dad JB who was captain back in 1971/72.
Darragh made a timely return from a spell in Australia in January, scoring a try in a home win over Clontarf to help St. Mary's in their bid to avoid relegation from Division 1A after a difficult start to their Ulster Bank League campaign.
Fanning, who is 26 and offers a sizeable presence on the wing at 6ft 3in and over 16 stone, has played for Connacht in the RaboDirect PRO12 and Amlin Challenge Cup. He also enjoyed a successful two-year stint Down Under with club side Tuggeranong Vikings.
His strong form for St. Mary's in the second half of the 2012/13 season earned him call-ups to the Ireland Club team - he played against the England Counties and Scotland Clubs - and the Leinster 'A' side.
St. Mary's won their first Ulster Bank League title in 2012, but finished eighth in the table this past season and will be determined to get back challenging for the trophy next term.
Under head coach Hugh Hogan, they did manage to win the Leinster Senior League Cup last December and finished as runners-up to Cork Constitution in the Ulster Bank Bateman All-Ireland Cup.
Peter Smyth and James Norton have the coaching reins for the new campaign which begins with the defence of their Leinster Senior Cup crown - they face Bective Rangers at Templeville Road in their opening fixture on August 24.
Related Links -