WATCH: “17, what the f**k?”: Mats Hummels reacts to hearing opponent’s age

Last night Mats Hummels was stunned to hear that an opposition winger who caused him endless problems on the field was a mere 17-years-old.

The defender was playing away with Borussia Dortmund in the Europa League last night, and the Germans had an unexpectedly difficult night against Norwegian side Odds BK.

The Norwegians led 3-0 after 22 minutes of play.

The visiting side fought back to win the game 4-3, but Dortmund captain Hummels was full of praise for his opponents afterwards.

“Left wing and right wing really good,” he said in the post-match interview. “Left wing fast and really a nice player.”

The player he singled out was Rafik Zekhnini, who only broke into the Odd first team this season.

As Hummels finished up the interviewer told him Zekhnini was 17.

“Really?” Hummels asked. “He’s really 17-years-old?

“What the f**k!”

The shocked reaction is a serious compliment to receive from a World Cup winner, we bet Zekhnini is buzzing after seeing the clip.

H/T balls.ie