Ruddock has heaped praise on Delport, who also previously enjoyed a stint at Gloucester, as he hits a memorable milestone in his career in England.
"Thinus is the ultimate professional, a great player who has played some fantastic rugby this season, many would say the best of his career," said Ruddock.
"He is Mr Dependable and Mr Reliable for us, a great role model for the rest of the squad. Off the field he is one of the nicest guys you will ever meet and you can see why the fans like him so much, he endears himself with his skills and his personality.
"He will want to turn in a great performance today to mark his 100th appearance in the top-flight and everyone at the club wishes to congratulate him for hitting this important milestone."
New Zealand international Rico Gear is ruled out with a virus and Wales international Chris Horsman has an ankle injury.
Fly half James Brown again misses out with a back problem and Joe Carlisle, a late withdrawal at Sale through illness, is named on the replacements bench.
Warriors v Leicester Tigers
15 Thinus Delport
14 Marcel Garvey
13 Dale Rasmussen
12 Sam Tuitupou
11 Miles Benjamin
10 Shane Drahm
9 Matt Powell
1 Tony Windo
2 Aleki Lutui
3 Tevita Taumoepeau
4 Greg Rawlinson
5 Craig Gillies
6 Tom Wood
7 Pat Sanderson (c)
8 Kai Horstmann
16 Matt Mullan
17 Shaun Ruwers
18 Will Bowley
19 Drew Hickey
20 Ryan Powell
21 Joe Carlisle
22 Chris Pennell
