A fully-antlered stag hurdled a fence before disrupting a children’s football match at Bushy Park Sports Club.
Breeding season, also known as rutting season, takes place from September to November and leads to male deer becoming increasingly territorial and aggressive.
This can also lead to incidents like the one that occurred at the club in Teddington, on 9 October, where a stag was chased by a rival onto a football pitch where children were playing.
Giedrius Stakauskas, 45, had been following the stag before it ran onto the pitch.
He said: “I heard some children screaming and crying. Some children ran away. The game was stopped. Some adults were filming the deer with their mobile phones.”
The stag had been chased by a rival male before hopping over a fence and stalking around the pitch for 10 minutes.
The game was halted before the fearless pitch invader ambled off into the trees.
“The stag started to bellow and slowly crossed the pitch. He wasn’t aggressive at all,” Stakauskas added.
Stakauskas, who is an amateur photographer, admitted the Bushy Park pitch invasion was the first he’d seen from a stag.
He explained: “I’ve photographed deer at Bushy Park for about 10 years and I have never witnessed such an encounter, I was really surprised.
“It was a very unusual moment to see a red deer stag bellowing on the football pitch during the children’s game.
“I was very lucky to witness this.”
It is currently rutting season, with male deer competing for breeding rights until November.
People visiting Bushy Park and Richmond Park have been advised by the Royal Parks to be extra vigilant during the deer rut and to keep a minimum distance of 50m away from the testosterone-fuelled stags.
The Royal Parks also advise people to keep dogs on leads or to walk them somewhere else, to not feed or touch the deer, take close-up pictures of the deer or to get in between two rutting male deer.
At the beginning of October, a video circulated online that showed photographers getting too close to the stags.
One stag with sharp antlers was so disturbed by the encroachment that it was forced to walk away.
Bushy Park manager Phil Edwards said: “Of course it’s disrespectful to get this close to wild animals, however what I really struggle to understand is why these photographers are taking such obvious risks with their own safety.
“They can weigh upwards of 25 stone and travel up to 30mph, so getting hit by one is the equivalent of being mown down by a motorbike.”
There have been cases of rutting deer injuring the public in the past.