Arsenal fans were in shock after seeing what he was doing.

Arsenal fans on social media could not believe what they spotted new signing Riccardo Calafiori doing during their Champions League match on Tuesday.

The Gunners won their first European match of the season on Tuesday as they beat French champions Paris Saint-Germain 2-0 at the Emirates Stadium.

Kai Havertz put Arsenal in the 20th minute before captain Buakyo Saka doubled the host’s lead shortly before half-time with a breathtaking free kick.

But the one moment that has everybody talking came from new Arsenal defender Calafiori who was spotted doing something strange during the match.

As he was being shown a yellow card in the 76th minute, Calafiori was handed something by teammate Declan Rice, and the defender immediately put it into his mouth, leading some fans to believe that it was a vape.

Reacting to the clip on social media platform X, one fan wrote: “Yo did I just see Rice pass Calafiori a Vape as he got a yellow.”

Another added: “Riccardo Calafiori using a VAPE that was thrown onto the pitch in the Champions League tonight?! WTF”

While one joked: “PSG were so dead tonight, they had Calafiori taking vape breaks mid game.”

However another fan pointed out that, despite the appearance, it was almost certainly not a vape and instead was probably a sachet of energy gel

Responding to other comments, one noted: “It’s a sports/energy gel that players get to keep energy and electrolytes levels up during a game.”

While another frustrated fan wrote: “People giving Calafiori s*** after today’s game…guys…its an energy gel pack.”

Riccardo Calafiori joined Arsenal from Serie A club Bologna over the summer. (Image: Getty)

Energy gels are often used by players throughout elite sport as a way to recover or give yourself a boost during a demanding training session or match.

In football, players often take them during refreshment breaks but can choose to have one during any break of play.

After consuming an energy gel, the blood quickly absorbs the simple sugars inside them, giving you a spike in energy.

Each energy gel, typically contains 25g of carbohydrates, providing about providing about 45 minutes of energy, which is why football players often take them around half-time.