Mayo turned up the heat in the second half of this lively clash at Ballyhaunis yesterday and the win keeps James Horan's men on course for a possible final meeting with John Maughan's NUIG.
It looked an unlikely outcome as Mayo fell behind to three early points from Jonathan Dunning, Kevin Higgins and Donal Shine as Roscommon dictated the early terms.
However, Mayo managed to claw their way back into the game, mainly due to Roscommon's indiscipline which was punished by the in-form Mark Ronaldson.
Ronaldson finished the game with 1-7, including six frees, as Roscommon blew two golden goal chances in that first half and held a slender 0-7 to 0-6 interval lead.
But the goal which swung the game in favour of the winners came three minutes into the second half from Ronaldson, who rounded the 'keeper in soccer style to finish to an empty net and shoot Mayo into the lead for the first time.
Roscommon managed just one point in the second half and that came as early as the first minute from Fintan Cregg.
Mayo took over at midfield where the new partnership of James Kilcullen and Barry Moran held sway, but the eye-catching display of the game came from debutant full-back David Killeen, who overshadowed dangerman Shine, while Enda Varley, Andrew Farrell and Cathal Freeman were among the other newcomers to make favourable impressions on the new Mayo manager.
ScorerS -- Mayo: M Ronaldson 1-7 (0-6f), E Varley 0-2, A Farrell, A Kilcoyne,J Gibbons 0-1 each. Roscommon: D Shine 0-3f, K Higgins 0-2, J Connaughton, J Dunning, F Cregg 0-1 each.
MAYO -- K O'Malley; K Higgins, D Killeen, E Reilly; T Howley, L Keegan, R O'Connor; B Moran, J Kilcullen; I Rowland, C Freeman, A Farrell; E Varley, M Ronaldson, B Benson. Subs: R Feeney for T Howley, J Gibbons for J Kilcullen, A O'Malley for A Farrell, A Kilcoyne for Benson, C Hallinan for B Moran.
ROSCOMMON -- E McGinley; S Purcell, D Ward, S McDermott; C Beirne, N Carty, J Nolan; M Finneran, K Higgins; F Cregg, J Connaughton, S O'Grady; J Dunning, D Shine, C Cregg. Subs: J Carney for D Ward, J Rogers for D Shine, T Kelly for J Dunning.
Ref -- M Duffy (Sligo).