The superstar Saint was in awesome form on Monday night in his side's 11-point win over Carlton, taking 13 marks and booting three goals.
Despite his form as the competition's hottest player, Riewoldt is ranked at 87 in the Official AFL Player Ratings.
However Sanderson isn't taking much notice of the numbers, insisting it would be a huge challenge to stop Riewoldt at AAMI Stadium this weekend.
"He's in career-best form, he's arguably the best player in the competition at the moment – certainly the most influential," Sanderson said.
"It's really hard to stop him because he's got the marking power and the endurance to get up the ground and run.
"I used to have headaches coaching against him at Geelong when I was looking after their backline and I'm sure Darren Milburn (the Crows defensive coach) is going to have a few headaches too, looking for a way to contain him."
The coach said it would take Adelaide's best defensive trio to curb Riewoldt's influence.
Daniel Talia, Andy Otten and Ben Rutten are all in good form this season.
While Rutten has the physical stature to match it with St Kilda's skipper one-on-one, Talia and Otten's run will be needed to cover him up the ground.
"Talia, Rutten and Otten are all going to have to have a crack. I don't think one player on his own can shut Riewoldt down the way that he's running and his power at the moment," he said.
"We'll come up with a couple of different ways to beat him, but I guess most importantly is keep the ball in our half.
"You just don't want to give them any opportunities to give the ball to Riewoldt inside their forward 50.
"He's taking marks up the ground as well and when he was at his best he was doing that – working his opponent up the ground and then running them back inside 50 when they're exhausted."
Young gun Brad Crouch has recovered from a hamstring strain and is available for selection against the Saints, but Sanderson said the 19-year-old would play for West Adelaide in the SANFL on Friday night.
He said that with few injuries and after such an emphatic win over the Giants, he wouldn't make many changes to the side.
Harry Thring is a reporter for AFL Media. Follow him on Twitter: @AFL_Harry.
