First-half goals from Kim Bo-kyung and Lee Jung-hyub earned South Korea a 2-0 success over Canada in Friday's friendly in Cheonan.
Uli Stielike's side face Uzbekistan in a crunch World Cup qualifier on Tuesday, two points behind their opponents, who occupy the final automatic berth.
And the hosts warmed up for that meeting in satisfactory fashion here, as two goals inside the opening 25 minutes set them on their way to a comfortable triumph.
Kim broke the deadlock in the 10th minute, Canada goalkeeper Simon Thomas unable to keep the midfielder's toe-poked effort out, and the advantage was doubled quarter of an hour later.
Canada dithered in their defensive efforts to clear inside their own area, and Lee pounced on the loose ball with a right-foot shot into the bottom-right corner from 18 yards.
The visitors, beaten 4-0 by Morocco in their last outing a month ago, could have crumbled but instead began to pose problems in the final 15 minutes.
Substitute Steven Vitoria nodded wide at the back post from a difficult angle, shortly before Marcus Haber saw his fine header from Fraser Aird's cross glance the top of the bar.
Canada's substitute goalkeeper Jayson Leutwiler made impressive stops from Kim and Koo Ja-cheol in the closing stages but Stielike's men could not add to their lead and will now turn their attentions to Tuesday's huge clash in Seoul.