Robert Lewandowski reached 40 goals for the fifth successive season when he put Bayern Munich 1-0 ahead at Union Berlin on Sunday.

The Bundesliga's most prolific striker made no mistake with a penalty late in the first half, after Leon Goretzka was hacked down in the 39th minute by Neven Subotic.

It took him to 40 goals from just 34 appearances in 2019-20, with Lewandowski again proving his value to the reigning German champion.

Since netting a relatively modest 25 goals in his first season at Bayern in 2014-15, the Poland star has notched successive hauls of 42, 43, 41, 40 and Sunday's spot-kick took him to another 40, with the promise of more to come in 2019-20.

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Coach Hansi Flick has backed the Pole, who has 26 Bundesliga goals to his name this season, to challenge Gerd Muller's record of scoring 40 goals in a single Bundesliga season.

In their first game back after the coronavirus suspension, Bayern was the dominant side without being at its very best.

Lewandowski's influence fluctuated, but he remains the man to whom Bayern look for goals, and head coach Hansi Flick is confident there are plenty more to come in this campaign.

Bayern has just eight games remaining in the league, so it would take a supreme effort for Lewandowski to match or pass Muller, who set the record while playing for Bayern in the 1971-72 season.

But providing Bayern can offer him the right service, Flick does not discount it happening.

"Lewy makes a good impression, I think he is in top form," said Flick.

"Today we failed to incorporate him into our game as much and we have to do that better in general in our offensive game.

"He scored again, is at 26 goals, and has eight games left to break Gerd Muller's record. That is not going to be easy but he has the quality.

"If someone can do it, it's him."

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Room for improvement

While he continues to be feted, Sunday saw Bayern leave room for improvement, as Flick acknowledged.

Its lead over second-placed Borussia Dortmund is back up to four points, however the teams go head to head later this month in a game that could yet threaten Bayern's momentum.

Flick said: "We had several opportunities to score, especially in the second half, but we didn't take advantage of them.

"Like for example on counter-attacks when we had some space. That's what we have to do better.

"Of course, we knew that at first not everything would go as planned. But the important thing was that we continued to resist and kept being concentrated and in the end won the game."

Bayern 2-0 win over Union Berlin also saw it reach the 50-goals mark under Flick in just 16 matches - a new Bundesliga record.