Scotland (28) 56
Rory Lamont inspired Scotland to a comfortable victory
Tries: Lamont 2, Parks, Dewey, Lawson, Southwell, Brown, Ford
Cons: Parks 5, Paterson 3
Portugal (10) 10
Rory Lamont scored two of Scotland's eight tries as they overcame a plucky Portugal in their opening World Cup match in St Etienne.
Lamont was well assisted by Dan Parks whose try and conversions added 15 points before he was replaced by Chris Paterson in the second-half.
Scott Lawson, Hugo Southwell, Kelly Brown, Ross Ford and Rob Dewey also ran in tries for the Scots.
Portugal scored their first ever World Cup try through Pedro Carvalho.
After a nervous start Scotland took the lead when full-back Lamont collected a short pass from captain Jason White and surged for the line, taking two Portugal defenders with him.
Parks kicked the conversion to give the Scots a 7-0 lead and Lamont got his second try two minutes later when he shrugged off challenges from Diogo Mateus and Jose Pinto to score.
Parks again converted and the early Scots nerves were replaced with a more confident side looking to attack the Portuguese down the right.
Rob Dewey powers past the Portuguese defence
Parks turned provider after 23 minutes when his diagonal kick was brilliantly caught by hooker Scott Lawson before he plunged over the line.
Portugal's joy at Carvalho short-range plunge was short-lived as Rob Dewey replied immediately with Scotland's fourth try.
The inside centre took a high kick and brushed aside two challenges to cross the line with ease.
Cardoso Pinto reduced the deficit with a penalty after White broke from a scrum early.
Scotland coach Frank Hadden was forced into a change when prop Allan Jacobsen suffered a calf injury, and he was replaced by Gavin Kerr.
Portugal flanker Joao Uva was then sin-binned for 10 minutes after persistent handling on the floor.
The game was peppered with handling errors and offsides
Scotland looked far from convincing after the break and Dan Parks was lucky not be punished when his pass to the wing was intercepted by Portugal's David Mateus.
Mateus sped to the try-line, but his joy was short-lived when referee Steve Walsh indicated he was playing advantage for offside.
Parks calmed Scottish nerves when he extended their lead after the Portuguese conceded a penalty at the breakdown, and from the resulting possession Simon Webster fed Parks to score.
Simon Webster then waltzed past four defenders before offloading to replacement Hugo Southwell, who scored in the corner.
Paterson converted before flanker Kelly Brown increased Scotland's lead with a try following good work by Rory Lamont.
Replacement hooker Ross Ford got the Scots' eighth and final try of the game when he grabbed a bouncing ball and sped past the tiring Portuguese defence.
Paterson added a conversion to give the Scots victory, but they will look to sharpen up for the game against Romania.
Scotland: R Lamont; S Lamont, Di Rollo, Dewey, S Webster; Parks, Blair; Jacobsen, Lawson, E Murray, Hines, S Murray, White (capt), Hogg, Taylor.
Replacements: Ford, Kerr, MacLeod, Brown, R Lawson, Paterson, Southwell.
Portugal: Leal; David Mateus, Sousa, Diogo Mateus, Carvalho; D Pinto, J Pinto; Cordeiro, Ferreira, Spachuck, G Uva, Penalva, Somoza, J Uva, V Uva.
Replacements: Mure, Correia, Murinello, Coutinho, Pissarra, Cabral, Portela.