Cardiff, Wales  - Germany stayed well on course for qualification for the World Cup next year with a 2-0 victory over Wales in Cardiff on Wednesday.

Michael Ballack blasted an opening goal for Germany in the 11th minute and Wales defender Ashley Williams diverted the ball into his net three minutes after the break.

It completed the double over Wales in Group 4 after a 1-0 home win and kept Joachim Loew's side four points clear of Russia who were 1-0 winners in Liechtenstein on the night.

Germany had beaten Liechtenstein 4-0 in Leipzig on Saturday.

"Our aim was to get six points from these two games and we achieved that," Loew said.

"I expected Wales to show some reaction after their defeat to Finland and it was important here in an away game to win on the way to 2010.

"In the first half we got into the game well and created chances and played with command at times. We wanted to get a quick goal after the break which we did but afterwards we slacked off a bit."

There were again no goals for Germany's Mario Gomez - in his 14th game for the national side with a blank - although the Stuttgart striker's cross led to Williams putting into his own net under no pressure to seal the points.

"It doesn't matter, we won and it was a goal," Gomez said.

"It was an own goal but that's not important. We wanted to win this game and we did, and that's the important thing."

The win leaves Germany well placed at the head of the group before matches against Azerbaijan in August and September and a visit to Russia in October.

Germany were soon in front when Ballack fired in a right-footer from 30 metres out after Wales were caught out by a throw-in they thought was theirs.

Wales responded well, with Robert Earnshaw foiled by Robert Enke in goal before a strong penalty appeal was turned down after Joe Ledley stumbled over Serdar Tasci, while at the other end Gomez fired narrowly wide and Lukas Podolski also had a good chance.

Gomez again worked hard and was rewarded minutes after the interval when he won the ball in a tussle with James Collins near the touchline.

There still seemed little danger to the Welsh defence when he he sent in a hopeful low cross, but Williams stuck out a leg to put the ball past keeper Wayne Hennessey into his own net.

Wales battled hard to get back in the game, and Earnshaw saw another effort well saved by Enke.

But it was Germany who looked the more dangerous and Bastian Schweinsteiger twice had good efforts, while Gomez had a late chance with a shot over the bar.

Wales, who were beaten 2-0 by Finland at home on Saturday, are now all but out of contention, with just six points from six games.

"I said before these two games we didn't have much to win from them but it was important we got the six points," Ballack said.

"From the playing point of view there is room for improvement."

Ballack was involved in an altercation on the pitch with Podolski in the second half but both players played down the incident.

Ballack said it was "a tactical" matter and that Podolski as a young player "still has a lot to learn" but the issue would be dealt with within the privacy of the team.

"As captain I have the right to raise things on the pitch," he said.

Loew said: "When Michael Ballack gives an instruction it has to be accepted, but I am sure it is something I will discuss with both of them." (dpa)