Manchester United manager Erik ten Hag acknowledged Casemiro's attacking output has taken him by surprise after the Brazilian scored twice in Saturday's 3-1 FA Cup win over Reading.
United booked their passage to the fifth round thanks to the straightforward victory at Old Trafford.
Despite the ultimately routine nature of the win, it took United 54 minutes to break Reading's resistance – the breakthrough came via Casemiro's impudent scoop following Antony's incisive pass.
Casemiro then got a second four minutes later, his long-range strike taking a slight deflection en route to the bottom-right corner, with Fred getting the third with a cheeky flick.
It was just the latest in a series of exceptional performances from Casemiro since his reported £60million move from Real Madrid in August, the brace taking him to four goals for the season.
@Casemiro is cooking!#MUFC || #FACup— Manchester United (@ManUtd) January 28, 2023
Add to that his five assists, and Casemiro's nine goal involvements for the campaign is the fourth-most in the United squad, while he also ranks fourth for open-play chances created (28).
When asked if he was surprised by Casemiro's impact in this regard, Ten Hag told ITV: "Yes. We know he's a great player. The midfield at Madrid with Toni Kroos and Luka Modric, it was great…
"I think he's capable of that [being an attacking threat]. We see offensively he's a part, and he enjoys it when he can come in [to the attack].
"What I like is dynamic football with variations and many positional switches, so we have to make the opponents think, so we can make the most."
United captain Harry Maguire credited the midfielder with having a transformational effect in several aspects.
"He's done what he was brought in to do," Maguire said. "He's a phenomenal player, he has been throughout his career. You don't win what he's won without being a top player.
"He's improved the team, improved the morale and improved the performance, and it's great to have him."