It's well known that 1D fans are a loyal, excited and very loving bunch, but during last night's concert in Amsterdam the excitement levels got a little too much.
Niall tweeted: "Can you limit what gets thrown on stage please! Coz something thrown at me tonight hit my knee! A lot of pain from it!"
It was particularly worrying for Niall as it was only this year he underwent surgery on his knee and was left on crutches for quite a while as he recovered.
Niall said: "Never wana sound like I'm complaining but only having my operation five months ago, I still get a bit of pain and I'm very scared about it."
Announcing the surgery in January, the 20-year-old star said: "Yes, I've had major knee surgery, a much larger surgery than first anticipated, but I would like to tell you it was a complete success! Considering the scale of it!"
He added to fans: "As It was a very important time for me and I didn't want to have fans knowing my whereabouts Needed privacy obviously."
One Direction's well-deserved time off at the start of the year allowed time for Niall to recover from the surgery (and take a breather following an insanely busy year), before the band began their mammoth world 'Where We Are Tour' last week.
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