No pain, no gain for Robert Lewandowski

A lean, mean goal-scoring machine and a Bayern Munich club legend in his own right, the indomitable Poland international has morphed into conceivably the most complete striker of his generation.

Watch: What makes LewanGOALski so special?

"I was small, short and very skinny," Lewandowski said of his teen years. "Everyone said 'you are too small, you won’t make it', but I wasn't going to give up!"

Given his parents' sporting accomplishments, Lewandowski was hardly short of inspiration. His father Krystof was a Polish Judo champion, who also played football in the Polish second division for Hutnik Warszawa, while his mother Iwona was a professional volleyball player.

Lewandowski had the pedigree, and what he apparently lacked physically, he more than made up for in attitude and application.

"His legs were so thin; I kept urging him to put some weight on and eat more bacon sandwiches," said Krzysztof Sikorski, Lewandowski's coach at Polish junior side Varsovia Warszawa. "It didn't stop him being a prolific scorer, though. I remember one season we scored 158 goals, and he got half of them."

The Polish capital remained Lewandowski's home throughout his youth career, until he was released by Legia in 2005. The Warsaw native was devastated, but the self-pity did not last. A move to Znicz Pruszkow - a club perched on the outskirts of the city - followed, and became the platform for a career pulled from the ruins of rejection.

Lewandowski finished top scorer in the third and the second division as unfancied Znicz won back-to-back promotions in 2007 and 2008. Legia weighed up a move to bring their former charge back to The Phoenix City, only for sporting director Miroslaw Trzeciak to pull the plug on the deal. "Who needs this lad when we're going to have Mikel Arruabarrena from Tenerife?"

(In)famous last words. Arruabarrena failed to find the net in six appearances for Legia, while Lewandowski fired Lech Poznan to the 2009/10 Polish league title with a league-leading 18 goals in his second season at the club. Not bad for a player Poznan coach Franciszek Smuda had likened to a "tree" on a failed scouting mission little over two years earlier.

The antithesis of wooden, Lewandowski continued his inexorable climb to greatness at Bundesliga giants Borussia Dortmund. He lifted the Bundesliga title in his debut season at the club, won a Bundesliga and DFB Cup double in 2011/12 and scooped his first Bundesliga Torjägerkanone prize a year later. He even made history as the first player to score four goals in a UEFA Champions League semi-final – against Real Madrid no less.

"I could tell right away that he was the most interesting player to come out of Poland for 20 years," explained then Dortmund coach Jürgen Klopp. "The potential was there and could easily be developed, if he had the right attitude. That is exactly what happened. It was clear he wanted to reach the top, and that was all I needed to know.

"He has all the skills you want from a striker, particularly physical strength and great finishing. But he also has the technique of a gifted midfield player. When he gets the ball in the middle of the pitch and distributes it to the wing, it's like watching a playmaker. The ball is his friend."

The nature of Lewandowski's eventual departure underlines just how invaluable he was to the Dortmund cause. Rather than naming their price for the coveted hitman, BVB insisted on the Poland captain seeing out the remainder of his contract before crossing the divide to join Bundesliga rivals Bayern on a free transfer in July 2014.

Anathema for some, a natural step for others – Lewandowski has cemented his legacy in the company of German football's most successful club.

After enjoying yet another debut campaign title win in 2014/15, he served up a season-long procession of goals during 2015/16 – becoming the first player since 1977 to break the 30-goal barrier in the Bundesliga and only the second in a Bayern shirt after club legend Gerd Müller - a feat he repeated in 2016/17.

Among his celebrated collection of 2015/16 strikes was an historic five-goal salvo in the 5-1 win over Wolfsburg that set Guinness World Records for: the most goals scored by a substitute in the Bundesliga (five); the fastest Bundesliga hat-trick (three minutes and 22 seconds); the fastest four goals in a Bundesliga match (five minutes and 42 seconds) and the fastest five goals in a Bundesliga match (eight minutes and 59 seconds).

He has also clocked up a century of Bundesliga goals faster than any other non-German player (168 appearances); is the first to rattle off 100 competitive strikes at Bayern's Allianz Arena; and is the Bundesliga's leading foreign scorer - as well as the fifth overall (197 goals in 281 outings).

Watch: All nine minutes of Lewandowski's five-goal haul against Wolfsburg

Yet for all the unadulterated success and clamor, there is no inflated ego. Husband to Anna - a bronze medal winner at the 2009 Karate World Cup - and Dad to Klara, Lewandowski entertains very few of the celebrity trappings associated with the latter-day footballer. The spotlight is only his when he is on the pitch.

"He is the most professional player I have ever met," enthused former Bayern tactician Pep Guardiola. "In his head, he thinks about the right food, sleep and training: 24 hours a day. He is always there, never injured, because he focuses on these things. He always knows what is important to be in the best condition."

Watch: Lewandowski's rise to global stardom

While it is difficult to imagine Lewandowski gorging on a bacon roll, it is fair to assume the early career setbacks and very personal critiques played a telling role in his development. He might be the ultimate hard gainer, but Bayern's peerless No.9 is the model professional and ne plus ultra of prolific modern strikers.

Chris Mayer-Lodge