The 13th-ranked Eagles spanked Southwestern, 25-17, 25-17, 25-10, in a quick 70-minute match at Johnson Hall.
Kirkwood trailed early in the second set when Williams put Madi Wagaman onto the floor as a setter and the 5-foot-9 freshman from Springville helped spark the team.
"That's the first time she's been put into the driver's seat to run the show without us having a big lead," said Williams, who liked the way Wagaman responded. "Madi does it every day (in practice) on the other side of the net. I felt confident in her."
Wagaman did not play in the first set, but she joined the rotation for the rest of the night and finished with 10 assists, two kills, two digs and two blocks.
"We're looking at some different possibilities in what we have in our substitution rotation," said Williams. "It's good to see some other kids go out there and be able to add something.
"We just need to get some kids some experience, because you never know when somebody is going to have an off-night and they have to be ready to go."
Kirkwood raised its records to 13-3 overall and 2-1 in the conference. Southwestern fell to 3-11 overall and 0-3 in the league.
Kirkwood hosts Indian Hills in a non-conference match Thursday night at 6:30.