Jenas and Modric played in midfield together at Spurs, though the Croatian has gone on to hit even greater heights, winning the Champions League four times and La Liga once with Real Madrid.
The Los Blancos star and his Croatia side stand in the way of England and their hopes of reaching their first World Cup final since 1966.
And Jenas, who now works as a pundit for the BBC, thinks England must negotiate a tie featuring the best midfielder in the world football if they are to get there.
“For England to beat Croatia and reach the World Cup final, they must stop the best midfielder in the world,” Jenas told BBC Sport.
“That is how highly I rate my former Tottenham team-mate Luka Modric. I’ve not met many players as driven as Luka, and I’ve seen even fewer who are as talented as him.
“The pressure is not a problem for him, though. Even in his younger days, in Croatia, he was like a god over there – he was seen as the next star to follow the likes of Zvonimir Boban and Robert Prosinecki.
“Now he is probably looked upon as the greatest Croatia player, which is some statement, and he is carrying the country’s hopes.”
Croatia have never been to a World Cup final, though they reached the semi-finals in 1998 with a team featuring the likes of Slavan Bilic and Davor Suker.
Modric will feature in a midfield that consists of the likes of Barcelona’s Ivan Rakitic, while Mario Mandzukic, Ivan Perisic, Mateo Kovacic and Dejan Lovren are just some of the names in a Croatian team expected to be England’s toughest test yet.