A system and method of trading combined orders in an exchange configured for trading by a combination of electronic and open-outcry trading mechanisms is provided. One method includes receiving an incoming order having a first order component and a second order component at an electronic trade engine and routing the first and second order components to a first electronic database. The first and second order components are matched and executed against order components maintained in the first and second electronic databases, respectively. Any unexecuted first and second order components are placed in an electronic book according to a predetermined program if the first or second order component cannot be completely matched against any order components maintained in one of the first or second electronic databases. The system includes a trade engine configured for receiving combined orders from market makers.