Preston Lodge were pushed all the way by Portobello before edging them out and keeping up their unbeaten start to the RBS East One season on Saturday.
At Cavalry Park, PL got off to a flying start and had built up a 16-0 lead at the interval thanks to a try by Rory Monks and three penalties and a conversion by Andy Clark.
Portobello were a changed side after the interval and a penalty by Chris Britee-Steer and a try by Fraser Boyter got them to 16-8 behind before PL held on for the victory.
Livingston have also won six from six and top East One after a 33-19 victory at Berwick.
North Berwick edged out RHC Cougars 20-16 with tries for the East Lothian side coming from Kyle Hamilton and Teddy Knight with Grant Craig and Liam West sharing the kicking points.
Dunbar beat Duns 13-3 while Linlithgow went down 15-7 at Langholm.
In RBS East Two performance of the weekend belonged to Edinburgh Northern. Prop John Leatham was the talk of the club after bagging a hat-trick of tries in the 85-3 win over Ross High.
Forrester defeated Dalkeith 25-19, Trinity Accies got a draw at Hawick Linden, but Lismore lost 54-0 at Hawick Harlequins.
Inverleith have 30 points out of a possible 30 in RBS East Three, this time beating Penicuik 24-8. Queensferry, Leith, Broughton and RDVC also won on Saturday with Queensferry impressive in their 61-17 victory at Walkerburn.