Brothers Joseph and Donnacha O'Brien were in double-winning form at Roscommon as Best Not Argue delivered in division one of the Alice Farrell Memorial Handicap.

The six-year-old mare was having her first start for Joseph O'Brien and was coming off a break of 324 days.

She was last approaching the straight and came wide before making headway at the two pole.

You couldn't have called her the winner a furlong out when she was fifth but she was soon ridden by Donnacha O'Brien and thundered home to get up in the closing stages by half a length.

O'Brien put up 2lb overweight on the mare who sported a first-time hood. Piper Bomb had to settle for second at 7/1, with Bittern Cry five lengths adrift in third at 11/1.

Jockey O'Brien said: "She is not a filly I know a whole lot about but she has done that nicely today.

"She is fairly versatile (ground-wise) and it's not that slow out there, it's good ground.

"It's her first run for Joseph and it's nice to get a win into her and hopefully she can win again."

Best Not Argue won two races for her former trainer John Murphy

Additional reporting by Thomas Weekes