The club comes off the back of a good win against Harlequins last weekend but the injury to Kevin Sorrell means new recruit Mark Bartholomeusz fills the gap.
The former Wallaby – who played alongside Kafer at the ACT Brumbies – will partner Ben Johnston in the midfield.
Meanwhile, in the pack Alex Codling and James Parkes retain their places in the starting line-up as does scrum-half Patrick Phibbs for the tricky away match.
"As I've said before, I think it's important to reward the players for performing well and keep the unit developing," said Kafer.
"I thought we improved against Quins on Sunday and we've been working hard on picking up on the development of the areas where we were not so good.
"James Parkes keeps his place after putting in a lot of hard work, in fact the players voted him as the players' player on Sunday.
"We're facing a difficult game up at Leeds who are a very strong side. They've got an abrasive pack and have a lot of pace out wide so we're going to have to be at the top of our game to compete.
"We're still unbeaten at home but want to improve our away performances to pick up some momentum and confidence."
Saracens: 15 Thomas Castaignède, 14 Richard Haughton, 13 Mark Bartholomeusz, 12 Ben Johnston, 11 Nathan McAvoy, 10 Andy Goode, 9 Dan Kirton, 8 Taine Randell, 7 Ryan Peacey, 6 Tony Roques, 5 Kris Chesney, 4 Simon Raiwalui (captain), 3 Emiliano Bergamaschi, 2 James Parkes, 1 Steven Sparks.Replacements: 16 Andy Kershaw, 17 Joe Ross, 18 Johnny Marsters, 19 Ben Skirving, 20 Patrick Phibbs, 21 Paul Bailey, 22 Adryan Winnan.
Kick-off: 14.30 BST (13.30 GMT)