Fair play to both sets of players who gave it everything on a tough night for running rugby.
The home side took the lead after five minutes.
After a good attack into the Stewart’s Melville ‘22’ the visitors turned the ball over and looked set to clear. However, the clearance kick was blocked and Watsonians hooker Tom Johnson benefited to dive over and score.
Stewart’s Melville were served well by back-rows Tom Croy and Lewis Scott who were tackling hard and in the 20th minute their team scored a try.
It came from centre Ali Grieg who found himself some space on the left to touch down. Stand-off Michael Hanning converted.
Watsonians regained the lead in the 27th minute when Johnson scored his second try.
Full-back Andrew Chalmers then nearly added a third for Sonians in the 33rd minute, but he was stopped just short.
Back-row Jonny Neary did score one before half-time to make it 15-7.
Three minutes after the interval home winger Mark Bertram scored his side’s fourth try after a well-worked move.
However, a breakaway try from the visitors’ centre AJ Rennie, converted by Hanning, got them back into things before Sonians’ fifth try from stand-off David Blair.
Stewart’s Melville then had replacement Adam Howie yellow carded with 16 minutes remaining as the game drifted to a conclusion and Watsonians held on safely to progress.