change up

Verb

 * 1)  To throw a pitch at a much slower than expected speed.
 * He changed up on Wilson after three fastballs and struck him out.
 * 1)  To confuse someone by doing something unexpected or in an unexpected way.
 * I thought that we were going to study the project some more, but then he came back from the weekend and changed up, making it a top priority.
 * 1)  To vary.
 * 2) To change to a higher gear in a vehicle.
 * 1) To change to a higher gear in a vehicle.
 * 1) To change to a higher gear in a vehicle.