Scotland's hopes of making the finals evaporated on Thursday when their 2-2 draw with Poland in Glasgow meant they could not finish in the top three in Group D which saw Germany and Poland advance as the automatic qualifiers and Ireland secure third place.
Germany finished with 22 points, Poland 21, Ireland 18, Scotland 15, Georgia 9 and Gibraltar, who suffered a tenth straight defeat in their first qualifying campaign, 0.
As has been the case in many of their matches, Gibraltar defended well for the first 20 minutes or so, but once Chris Martin headed Scotland in front after 25 minutes, there was only going to be one outcome.
Shaun Maloney doubled Scotland's lead after 39 minutes, before two Fletcher goals inside four minutes early in the second half made it 4-0.
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Fletcher completed his hat-trick in the 85th minute before Steven Naismith added a sixth in stoppage time.
Gibraltar conceded 56 goals in their 10 games and scored twice, once when they lost 6-1 to Scotland in March.
(Reporting by Mike Collett; editing by Justin Palmer)
