The Borussia Dortmund players joined the supporters at the full time whistle as 'You'll Never Walk Alone' was sung by both sets of fans.
Marco Reus opened the scoring for the German side and admitted: 'On the pitch, we had no idea what was going on and were initially irritated by the silence.
"But, straight after the game, our coach Thomas Tuchel came to us and explained what had happened. It obviously put a shadow over the game and compliment to the fans for the way they behaved."
Borussia Dortmund president Reinhard Rauball told Sky Sports: "In the name of Borussia Dortmund, I wish to express my heartfelt sympathy and condolences to the families of those affected. Our thoughts are with them.
"We were informed pretty quickly in the stands of what had happened from that moment on, the game fell right into the background. I could no longer concentrate on it.
"The fans' reaction was spontaneous. I've never experienced anything like it. I can only pay a huge compliment to all of the fans for the way in which they expressed their sorrow and respect in this way, in a unified manner.
"I take my hat off to the Mainz fans who, without exception, joined us in mourning and stopped supporting their team.
"The scarves held in the air when 'You'll Never Walk Alone' was sung has my utmost respect. It shows how deeply rooted honour and respect of each other exists and can be expressed in such a short period of time, and I can only take my hat off to that."
Most Bundesliga clubs immediately showed their solidarity with Dortmund and paid their tributes to the deceased in response to a Tweet by Dortmund which confirmed what had happened.
Dortmund's players lined up arm in arm in front of the Sudtribune - South Stand - as You'll Never Walk Alone was sung by the entire stadium following the final whistle.
"Prayers & thoughts to the fan we sadly lost today at the stadium, as well as to our 2nd fan now at hospital," tweeted midfielder Henrikh Mkhitaryan while full back Marcel Schmelzer also paid his respects on social media.
- Daily Mail