What experience St Mary's brought to Angelsea Road last night with their skeleton crew was enough to secure their first Old Belvedere Floodlit Cup.
With their high-profile players absent because of Leinster's European Cup opener against Leicester on Friday, a tentative start was transformed into a strong finish as out-half Fergal Campion kicked three penalties and converted a Ray McIlreavy try.
Bective went into half-time only three points down after initially producing some stylish breaks, notably through their dynamic number eight, Paul Hatton.
But, in a difficult second half for Bective, St Mary's robust defence gave little away and squeezed any vigour out of the attack.
McIlreavy and Gareth Gannon in the centre formed a strong bridge for St Mary's, and second rows Eoin Keane and Ian Bloomer ensured there was little leakage in their domain.
While wing Dara Carney was lively and dangerous on the left, and Hatton always looking for a chance to make yards on the break, Bective simply didn't have enough in the final 40 minutes to unsettle their Division One opponents.
The icy and difficult wind suited Bective in the first half. Despite that advantage, Campion was first to score after 16 minutes. Bective then applied what looked like a useful weapon when a lineout was converted to a rolling maul and St Mary's went backwards with frightening ease. Tight-head Paul Kelly touched down and John Bresnihan converted for a 7-3 Bective lead.
The game was lively and competitive with both teams opting to please the crowd and run the ball. Third, fourth and fifth phase possession was not unusual, but both sides struggled to piece together defence-splitting runs.
Bresnihan added another kick for 10-3 before Campion replied to take the score to 10-6. It was then McIlreavy scythed through and into the left corner for a try, Campion coverting with ease for 13-10 at the break.
From that Bective couldn't recover. Playing into the wind and facing a composed St Mary's, the game was tight, and a spirited Bective was forced to chase the match.
Scoring sequence: 15 mins: F Campion pen 3-0; 19: P Kelly try, J Bresnihan con 3-7; 26: J Bresnihan pen 3-10; 39: F Campion pen 6-10; 40: R McIlreavy try, F Campion con 13-10. 76: F Campion pen 16-10.
BECTIVE RANGERS: B Cunningham; D Jackson (capt), D Lyons, C Curley, D Carney; J Bresnihan, B Free; B Crowley, S Farrelly, P Kelly, J Bulger, B O'Connnor, J Oliver, S Montgomery, P Hatton. Replacements: D Shaw for Bulger (57 mins); B Whelan for Farrelly (64 mins).
ST MARY'S: K McNamee; M Lavelle, R McIlreavy (capt), G Gannon, A Conboy; F Campion, P Lynch; N Foxe, D Lee, P Coyle, E Keane, I Bloomer, R Gavin, R Doyle, D Clare. Replacements: J Kilbride for Lynch (9 mins); G Hickey for Gavin (64 mins). Referee: A Rolland.
FLOODLIT CUP - Quarter-final: Athlone IT 47 (P Flanagan 2 tries, N Quinn try, J Houlihan 2 tries, A Nash try, B Dillon try, J Carey 6 cons), Creggs 8 (A Looby pen and try).