Morgan Mammosser bumped the ball Thursday night at Musgrove Fieldhouse. The ball floated into the air, then back down. Mammosser and her Rock Falls Rockets teammates watched it drop untouched on their own side of the net. Mammosser held her arms out in frustration, as the Rockets dropped Game 1 of the 3A Sterling Regional championship to Sterling. It got worse before it got better for the Rockets, as they fell behind 5-1 in Game 2. With their backs to the wall, the Rockets rallied, taking the next two games for a 20-25, 25-15, 25-17 win. They advance to play LaSalle-Peru at 7 p.m. on Tuesday at the 3A Mendota Sectional. “It took heart,” Mammosser said. “We definitely had our backs to the wall, but we knew we could play better. We had lost to them twice this year, and we hadn’t shown them how good we are. We wanted to show that tonight.” “We won that first set and went up 5-1 in the second set, and then just backed off for some reason,” Sterling coach Dale Dykeman said. Sterling swept both regular season matches in two sets. The Rockets (27-10) advance to the Mendota Sectional semifinals to face LaSalle-Peru (29-7) at 7 p.m. Tuesday. The Lady Cavaliers defeated Streator 25-16, 25-17 at Pontiac. The first semifinal pits Dunlap vs. Freeport. Class 2A: El Paso-Gridley knocked off top-seeded Fieldcrest 25-22, 22-25, 27-25 for the regional championship at St. Bede Thursday. Seneca rallied to defeat Sterling Newman 19-25, 25-11, 25-13 in 2A regional finals at Amboy. The Irish return home to host their own sectional. At Orion, the host Chargers defeated West Central Conference rival Sherrard 25-23, 22-25, 25-23 to earn a date to sectionals on the Rams’ home court.