Eight different Spartans scored in the win that improved the team to 13-2 this fall.
Tucker Simmons scored three first-half goals while Benjamin Kahler had two in the first half as Southwestern raced out to a 7-0 advantage. Cecil Newton and Michel Weisser also had goals ahead of the halftime break.
Jaime Gutierrez added a pair of second-half goals. Also scoring in the second half were Weisser, Kaden Barlow, Chris Claiborne and Michael Clements.
Weisser and DeMessa each had three assists.
Southwestern closes out its regular-season schedule Wednesday at Bethesda Christian.
In other prep events Monday:
Boys soccer
Indian Creek 4, Shelbyville 0
At Shelbyville, the visiting Braves scored three times in the first half and spoiled Senior Night for the Golden Bears (3-12).
Jude Heaston, Denton Steenbergen, Aiden Long and Logan Jackson scored goals for Indian Creek (6-5-1). Long also had three assists.
Girls soccer
Whiteland 4, Triton Central 0
At Triton Central, the visiting Warriors scored three first-half goals to take a lead they would never relinquish.
Whiteland improved to 9-5-1. Triton Central dropped back under .500 at 6-7.
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