Germany head coach Joachim Low admits he is not completely satisfied with his side with just three months to go until the delayed European Championship finals.

Die Mannschaft cruised to a 3-0 win over Iceland in their opening World Cup 2022 qualifier on Thursday through goals from Leon Goretzka, Kai Havertz and Ilkay Gundogan.

It was a welcome win for Low's men, coming on the back of a 6-0 hammering against Spain in their final match of a poor 2020 that saw them win only three of their eight games.

Germany had 81.5 per cent of the ball, attempted 1,053 passes and had 15 shots compared to Iceland's eight, but Low feels there is plenty of room for improvement.

"I wasn't exactly full of praise for the whole game," he said at a news conference on Saturday previewing the trip to Romania.

"We could have done better in the second half in particular. If we look to the Euros, we have to improve in a few areas. 

"It was a good start and we had a lot of well implemented play. But I'm not yet completely satisfied."

Without the influential Toni Kroos, who withdrew from the squad with a knock, Germany's midfield three of Gundogan, Goretzka and Joshua Kimmich impressed against Iceland.

Jamal Musiala made his debut as a second-half substitute in Duisburg, while Borussia Monchengladbach's highly-rated Florian Neuhaus was also introduced for his fourth cap.

But Low insists Kroos, who remains a regular for Real Madrid, is still integral to his plans.

"The midfield set the tone against Iceland, everyone in their own way. I'm happy about that. But Kroos is a player with immense value to us," said Low, who will end his 15-year tenure after Euro 2020.

"Our strength at major tournaments has been players coming off the bench. We have good players in midfield - any team who wants to achieve something needs that."

Germany's win over Iceland was their 17th in a row in World Cup qualifying, setting a new record and placing them top of Group J ahead of Sunday's trip to Romania.

Niklas Sule has been ruled out of both that match and Wednesday's visit of North Macedonia, while Robin Gosens is also out and Goretzka and Leroy Sane are carrying knocks.

Low does not intend to make many changes ​for the showdown at the National Arena as Germany seek back-to-back competitive wins for the first time since November 2019.

"I'm going to wait until tomorrow to see how things develop with Leon," Low said. "He is the first option in midfield and I hope he can play from the start.

"If he doesn't then it is possible to let Musiala play, or move Serge Gnabry deeper and bring in Timo Werner. Our usual defensive line will start."

Romania kicked off their qualifying campaign with a 3-2 home win against North Macedonia to make it four games without defeat, scoring 12 goals across those fixtures.

And Low expects to face an attack-minded side in Bucharest.

"They have great strengths on the attack and act much more aggressively than Iceland," he said. "We will face completely different challenges.

"I've seen Romania one time or another and we have a lot of information on them. 

"They have technically well-trained players who want the ball. They don't want to defend so much, but they want to play forward. I think Romania's central midfield is very good."