The Salukis (4-3) scored in each of the first four innings to back a stellar outing by sophomore right-hander Michael Baird. The Leathernecks (0-6) committed three errors and collected three hits in a 9-0 loss.
Baird (1-1) pitched six shutout innings, striking out a career-high nine batters and walking none.
"I was able to throw my fastball early in the count," he said. "Just being able to attack them early on in the count and not get behind them."
SIU struck first, scoring a run on an RBI single by junior right fielder Jake Hand before WIU sophomore lefty J.