On his 70th birthday, Gerd Mueller's record of 40 goals in a single Bundesliga season is 'still unbeatable' -- according to one of the strikers who could break it.

Mueller, dubbed 'the Bomber of the Nation' is being treated for Alzheimer's at a Bavarian nursing home as the Bayern Munich and Germany legend turned 70 on Tuesday.

During his career, Mueller finished as the Bundesliga's top-scorer on seven occasions.

No-one has ever come close to beating his record haul of 40 German league goals scored in the 1971/72 season -- until now.

Current Bayern striker Robert Lewandowski has so far scored 13 goals in 11 league games this campaign.

At the same stage of the season in 1971, Mueller had only scored six goals, while Lewandowski needed just nine minutes to score five goals against Wolfsburg in September.

The Poland hot-shot hopes to add to his tally of 17 goals in all competitions for Bayern this season at home to Arsenal on Wednesday in the Champions League.

But the 27-year-old insists Mueller's record over a 34-match league season is still a long way off.

"It's still too far away," said Lewandowski on Monday.

"You'd need to score two or three goals in every game, only then can you think about doing it.

"When you look at the league's scoring records, his name is almost alongside everyone.

"That shows what a great player he was."

Bayern won the title in the 71/72 season by 22 points with Mueller scoring five and four goals in two separate league matches.

He also scored a hat-trick on no less than four further occasions.

Lewandowski has already equalled one of Mueller's records this season by scoring ten goals after seven league games, set in the 1973/74 season.

"40 is a big number, but with Robert in this kind of form, anything is possible," Lewandowski's team-mate David Alaba said earlier this season.

But the Poland international is not the only current Bundesliga star who could challenge Mueller's record this season.

His Bayern team-mate Thomas Mueller has scored ten goals in 11 league games, but says it will take a phenomenal effort to break Mueller's record.

"He (Lewandowski) has set the bar high for himself and it would be good for us all if he could maintain it," said Mueller.

"But realistically there will be games when he'll only score one or none."

Alongside Lewandowski, Gabon striker Pierre-Emerick Aubameyang is the league's joint top scorer with 13 goals for Borussia Dortmund.

He says his target is simply keeping up with Lewandowski in the battle for the Bundesliga's 'Golden Cannon' awarded to the league's top-scorer.

"Lewandowski is one of the best strikers in the world at the moment", said Aubameyang after scoring a hat-trick against Augsburg ten days ago

"I'm trying to do better than him, but I can only try.

"It's been a good start (to this season), but it's going to be difficult to over-take Gerd Mueller," he added.

One Mueller record which is good for another season is his incredible haul of 15 goals after just ten games in the 1968/69 season.

He went onto claim 30 goals in 30 league games.

Mueller's overall records are dazzling with 533 goals in a total of 585 games for Bayern.

"Gerd Mueller is one of the greats of world football," said Bayern chairman Karl-Heinz Rummenigge.

"Without his goals, FC Bayern and German football would not be where it is today."