Metea Valley 5, Hinsdale South 1:
The 12th-seeded Mustangs (17-14) broke a 1-1 tie by scoring 4 runs in the top of the seventh and upsetting No. 5 Hinsdale South (22-10) in the Class 4A Oswego regional semifinals. Michael Mooney's RBI single broke the tie and then Andy See added a sacrifice fly and Tamal Kumar doubled home 2 insurance runs.
Downers North 4, Plainfield Central 1:
The Trojans (20-11) scored all their runs in the bottom of the sixth to break a scoreless tie and advance to the Class 4A Oswego regional final. Matt Zaboudil doubled in the game's first run and Joe Provenzano followed with a 2-run single. Mike O'Malley scattered 5 hits in a complete-game victory.
Yorkville 5, WW South 4:
The Tigers (18-15) led 4-3 after five innings before Yorkville rallied with 2 runs in the top of the sixth to pull out the victory in the Class 4A Romeoville regional semifinals. Rich O'Neil doubled and drove in 2 runs for WW South while Eric Giltz went 2-for-3 with a triple.