With a number of players out injured or not available Langholm had to reshuffle things and a number were playing out of position.
Portobello applied plenty pressure from the kick-off but failed to make the break through and it was the hosts who took the lead after seven minutes with a try from fullback Jamie Little.
Portobello hit back and a wide attack secured an unconverted try after 14 minutes.
Both sides had periods of pressure and eventually Martin Chisholm put Langholm back in front with a penalty goal and the hosts widened the gap when prop Steve Jardine charged through from 30 metres for a try at the posts which Chisholm converted for a 15-5 half time lead.
Lack of games seemed to affect Langholm and It was all Portobello in the third quarter as they ran in three tries, two of which were converted, bagging a try bonus in the process.
Langholm made a number of changes and fresh legs seemed to help. A good move involving both backs and forwards resulted in a try for Eddie Turner which Chisholm converted to close the gap to two points.
With less than 10 minutes to go however Portobello kicked a penalty then added a converted try and Langholm finished with no reward.