Arsenal's Lucas Torreira "becomes crazy" when he enters the pitch and the defensive midfielder's shift in mentality is "like Transformers", according to Sokratis Papastathopoulos.
Despite his struggle to hold down a place in Unai Emery's first team, Torreira has had a big impact on team-mate Sokratis, who has been ever-present for the Gunners in the league this season.
"When he is off the pitch he is so calm but when he is on the pitch it is like Transformers - he becomes crazy!" Sokratis told the club's official website.
"He works very well. He is small but he is strong enough.
"I like him very much because he gives everything, he tries to defend every time and when we have players who do this work in front of us, it is very important."
After suffering back-to-back defeats in their opening two games of the season, Arsenal have recovered their form and put together a sequence of four consecutive Premier League victories.
Sokratis said improvements in defence were key to Arsenal's resurgence and indicated that Emery's side is already beginning to gel.
"[The defensive unit] is getting better and better every month," said the Greece international.
"It is not just the defence but the whole team: how we work, tactically, in the offence and the defence.
"We are getting better."
The Gunners face off against Watford at the Emirates on Saturday, which is a must-win game for the hosts if they are to catch up with the Hornets in the table.