"Rüdiger has become more aggressive," Souness told The Times.
"In the second-last league game of last season, against Leicester City at Stamford Bridge after Chelsea had lost the FA Cup final to them, he went through a few Leicester players in the first five minutes to put a marker down and now looks to be bullying people.
"He’s laying it on the line, saying, “Does anyone fancy taking me on?” and his team-mates are responding to that."