On Tuesday, Tuilagi was named in England’s 25-man squad to play New Zealand on Saturday, live on Sky Sports.
When asked if the 27-year-old had the X-factor, Youngs told Sky Sports News: “Yes, I don’t know another player like it.
“You need game-breakers don’t you? You know against New Zealand you’re going to have score tries, simply trying to slot penalties probably isn’t going to be enough because of the threat they pose.
“So having guys like him and other guys is vital because you need guys that are going to be game changers or game-breakers and he’s certainly one of those guys, so he’s going to be important if he’s involved.”
Tuilagi has been blighted by injury and last played for England two-and-a-half years ago but is fit to play this weekend.
Youngs added: “He’s looking good in training but I don’t make those decisions if he plays or not, I just know what he’s capable of and I’m sure if he’s given the opportunity that he would be able to certainly give us a lot of go-forward and be a key cog to this team.”
Tuilagi delivered one of his best performances which inspired England to beat the All Blacks 38-12 at Twickenham.
Youngs says England are confident they have the ability to produce another memorable victory.
“Our belief is very good,” he said. “We’re really excited about the opportunity and I’m very excited and I know that my team-mates echo that as well. We’re looking forward to being at Twickenham and we’re in a good place.
“I think it’s important to recognise that there’s a reason they’ve been so dominant for years.
“They’re highly successful, you can’t hide away from that but it’s important you really focus on what we can do.
“We don’t want to get lost in what they do and how they play and everything like that.
“We want to make sure that we give the best account of ourselves and how that is, is making sure we get our game-plan clarity absolute right and then we’re able to execute on Saturday.”