Kevin Volland struck twice in three first-half minutes to take the wind out of Irish sails as Germany cruised to another comfortable Group 10 win in Sligo.
Already ahead through Moritz Leitner, TSG 1899 Hoffenheim forward Volland struck in the 22nd and 24th minutes to put the visitors well in command. Samir Carruthers was dismissed after the break for the hosts before Philipp Hofmann rounded off a second simple win in four days for Horst Hrubesch's charges.
With Ireland themselves coming off a big win in the Faroe Islands things were not expected to be easy for the visitors, but the hosts gave Germany a generous hand. On 12 minutes Leitner collected a clearance 25 metres from goal before zipping off a shot which keeper Aaron McCarey allowed to slip under his body.
A defensive mix-up presented the visitors with a second as Anthony O'Connor sliced an attempted clearance over the outrushing McCarey which allowed Volland to head his first into an empty goal. Moments later Amin Younes' trickery on the left bought him enough room to whip in a cross which the No9 met at the front post and guided into the net with a precise header.
Carruthers's second yellow on 61 minutes triggered further intense pressure on the home goal, and Germany got the fourth their dominance deserved on 83 minutes when substitute Hofmann hammered a low shot into the net, securing an early three-point lead in the section for his side.