Justin Bieber: Poland Concert Pics!

Justin Bieber shows off his toned arms as he belts on stage during his concert on Monday night (March 25) in Lodz, Poland.

That same day, the 19-year-old singer wished his mentor Usher good luck on his Voice debut, which premiered that night.

PHOTOS: Check out the latest pics of Justin Bieber

“@UsherRaymondIV @NBCTheVoice good luck tonight big bro,” he tweeted. “CRAZY SHOW!! Thank u POLAND!”

Justin recently posed for a cool photo shoot for adidas Neo’s new virtual lookbook.

25+ pics inside of Justin Bieber performing in Poland…