The Dortmund boss is delighted with how his star striker has performed in recent months but is confident his side can cope when he leavesJurgen Klopp has hailed Robert Lewandowski but is confident that Borussia Dortmund can cope when he leaves for Bayern Munich.
The Polish striker put in a man-of-the-match performance for the Bundesliga side during the 2-1 win over Wolfsburg on Saturday to ease BVB towards a Champions League place.
His long-awaited free transfer to the Allianz Arena was confirmed back in January but Klopp is confident that other players can step into the void he leaves.
"Robert has developed so much, but other players can and will do that at this club," he told reporters.
"It was a big win today. We showed a really good mentality to win it after a Champions League match. On Tuesday, we need to play like we did in the second-half twice.
Kevin Grosskreutz has played in a variety of different positions this term and Klopp is thankful for how the Germany international has coped.
"We ask a lot of Kevin, playing in so many positions. He got much better as the game went on."
Meanwhile, Marco Reus believes his side could come unstuck if they play against Real Madrid in midweek as they did in the first half, as they look to overturn a 3-0 deficit from the first-leg.
"The game in Madrid took a lot out of us and we didn't play well in the first half. But it was really great to win.
"If we play against Real Madrid as we did in the first half today, it will be tough, but anything is possible."
Reus' opportunistic winner came after Wolfsburg keeper Max Grun spilled the ball, much to the youngster's dismay, but the former Gladbach man insists he committed no infringement.
"Sometimes the keeper and defender get in each other's way," he added.