Both men were on the books at Stadio Olimpico last season, with their respective exploits drawing admiring glances from England.
Salah has gone on to flourish at Anfield, with a £36.9 million transfer fee made to look quite the bargain by a 43-goal haul which has sparked Ballon d’Or talk.
Rudiger has not been as impressive following a £29m move to Stamford Bridge, leading to a recent dropping by Antonio Conte, but he is ready for a battle with a man he knows well.
Liverpool are due in west London on Sunday, with it likely that Salah will once again lead the charge for the Reds despite Jurgen Klopp’s side now having a Champions League final to prepare for.
Rudiger could be forgiven for fearing a meeting with a forward performing at the peak of his powers, but the Germany international believes he boasts the necessary qualities to contain a fearsome foe.
He told Football Focus: “If I play, it will be a direct duel against Salah. The good thing is, I’m not slow!”
Whatever happens this weekend, Rudiger is delighted to see a close friend prospering at Liverpool.
He admits that he never expected things to go quite so well for Salah on Merseyside, but always believed that a humble performer would see his potential fully unlocked somewhere.
Rudiger added: “He’s the most polite guy I have ever met in football. He’s a fantastic person.
“Of course you are always a bit surprised but I know his ability, his potential and I knew he would be good for Liverpool.”
Salah did find the target when Liverpool took on Chelsea at Anfield back in November, in a 1-1 draw, but Rudiger played no part in that encounter and will be looking to secure a clean sheet this time around.