The Pole famously appeared frustrated with the teen at one stage last season, but the pair now appear more insync on the pitch this term.
He said on the Rio Ferdinand Presents podcast: "First time when I saw him on our training session, he was 15, really 15. And first time in my life I saw someone, because I saw a lot of young, talented players, but first time in my life I saw that I have inside this, wow, who is it? You know, I saw the players, oh, he has good...
"You know, it's a little bit, about (ex-Bayern Munich teammate Jamal) Musiala, also he had something, you know, but Lamine, the first thing I was, wow, this guy is like... How is possible in this age? He's already on this kind of level, you know, and even that he was 16 years old, that was still like, come on, it's impossible to be so good, so clever also in this age.
"But I always try to give him maybe some kind of advice that for one side, it's amazing what he did, what he's doing, but also you have to think that soon for him will be the huge challenge to stay on this level or maybe do the next step. And it's not about the next two, three years. We are talking about next maybe 10 years that he should be thinking about what he should do to be on the top like 28, 29, 30 or even longer. And that I think for him is the biggest challenge of his career."
On offering leadership to today's young generation of players, Lewandowski also said: "I don't think that maybe in the new generation, you have to be different a little bit, you know. The new generation, you have to more take care of them, you know.
"Like 15 years ago, if you're being like more stronger, that was for me when I was young. Okay, I want more. I'm not afraid that someone will shout at me, you know. I was more motivated later. And now I'm not sure that the young players are ready for this kind of shouting from the coach.
"Yeah, because it's like, but it's not about football. It's general in the world, you know. You have to be more like, more nice, you know. And I don't think that the young players now like if someone's shouting at them. It's like, you know. But not only in football. Yeah, yeah.
"But in general, in the world, the life looks like that. So you have to also change that. Sometimes from this generation, for me, it was like very motivating someone shouting at us, you know. And now it's like you have to find the balance. I don't want to say that you cannot speak loud or, you know, speaking more strongly. No, no, but sometimes you cannot always shout like sometimes before was, you know…"
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