Joachim Löw is alarmed by what he sees rolling off the Bundesliga production line. His rivals will share that sentiment in Russia next summer after Germany secured their place at the World Cup finals with a flawless qualifying record and a swift, convincing defeat of Northern Ireland.

Superb early goals from Sebastian Rudy and Sandro Wagner inflicted a first competitive home defeat on Michael O’Neill’s team in more than four years while demonstrating the depth of class at Löw’s disposal, despite his suggestions to the contrary. Germany arrived in Belfast minus several established names but departed with their remarkable 83-year unbeaten record in away World Cup qualifiers extended to 47 matches.

Victory for the world champions was not in doubt from the moment Rudy scored his first international goal in the second minute. The outstanding Joshua Kimmich gave them a three-goal cushion late on but Josh Magennis’s stoppage‑time header may be more than a consolation for Northern Ireland should goal difference determine who qualifies for the play‑offs. Hopefully for O’Neill it will not come to that. Results elsewhere could deliver Northern Ireland a berth before they face Norway on Sunday. Germany, perversely, ensured the Irish will head to Oslo with confidence. “One thing I’ll say about playing Germany,” O’Neill said, “is that whoever you play afterwards seems a lot easier.”

The Northern Ireland manager added: “I’m not sure there is a system that can contain Germany. The quality of their play at times was breathtaking. We had four Premier League players in our team and they only come up against that level of movement when they play the top teams. We also started with two players from League One, Championship players, and they had five Bayern Munich players in their starting lineup. It is a huge education for our players. I would imagine Germany will have a fantastic squad in Russia, possibly even stronger than four years ago. They have a never-ending conveyer belt of talent coming through.”

O’Neill had based his game-plan on containment, on staying in the contest as long as possible, and it was gone in 80 seconds. Meticulous preparation has been a hallmark of the Northern Ireland manager’s reign but little could have stopped the shot that put Germany ahead from their first attack. A five-man defence, however, could have done more to prevent Leon Goretzka crossing from the by-line unchallenged. Lee Hodson’s clearance was unconvincing, sliced straight to Kimmich, but the same could not be said of its return.

Michael McGovern can do nothing to stop Sebastian Rudy’s drive from outside the area after just 80 seconds. Photograph: Alexander Hassenstein/Bongarts/Getty Images

Rudy met his Bayern team-mate’s lay‑off with a pristine half-volley from 30 yards. The ball arrowed inside Michael McGovern’s top left-hand corner, kissing the post en route, to leave both sets of players stunned. It was the first goal McGovern had conceded in more than 10 hours and the first competitive goal against Northern Ireland in almost nine. It was also Kimmich’s eighth assist of the qualifying campaign – from right-back. “It was the worst start we could have had,” O’Neill admitted later.

That lead and a limited threat from the home side invited Germany to attack in numbers. At times they left only Mats Hummels and Jérôme Boateng in defence while the full-backs, Kimmich and Marvin Plattenhardt, operated as auxiliary wingers. Northern Ireland were besieged by a dominant, formidable opponent right through the first half.

Germany continued to prosper on the right and McGovern produced a fine one‑handed save to deny Wagner. The towering centre-forward struck a post with a diving header from Kimmich’s cross but could not be contained for long. Gareth McAuley afforded Wagner too much room when the striker collected Thomas Müller’s pass with his back to goal. He turned on to his left under minimal pressure and struck another fine shot beyond McGovern, this time to the goalkeeper’s right, from the edge of the area.

“We’re gonna win 3-2,” sang the resolute Northern Ireland support. The more realistic objective for O’Neill’s team was avoiding heavy defeat. It was to their credit, and due to the manager’s tactical switch at the interval, that they did so. Corry Evans had the home side’s only chance of note before the interval but the Barcelona goalkeeper Marc-André ter Stegen smothered his effort.

O’Neill introduced Stuart Dallas for Hodson at half-time and switched to a four-man defence, allowing Northern Ireland “to get tighter in midfield and get higher up the pitch”. And Conor Washington should have given his team unexpected hope when he turned inside Boateng but struck the crossbar from 12 yards out. Kimmich then volleyed home from Plattenhardt’s cross before Magennis converted from close range with the final touch of the game.

“We said when the draw was made that we wanted to dominate the group, make no compromises and possibly not drop any points,” Löw said. “So I am very satisfied. Are we going to allow the players to celebrate by having a beer in the Belfast pubs? No, that would be unprofessional and not our style.” Germany will stick to winning instead.