Purchase a ticket and join the fans at a game at Silverlakes Sports Complex. If there's nothing on while you're in the area, you might like to check if they offer a tour of the facilities.
You'll have no end of sightseeing choices when in Mira Loma. Silverlakes Sports Complex is an ideal place to begin here, but there are many other worthwhile attractions to discover. La Sierra University, Prado Regional Park, and Hidden Valley Golf Club are close to the sporting facility and and will cap off your day nicely.