Examples are disclosed to track sport implements and/or objects of interest. An example apparatus includes a first coil to generate a first magnetic field having a first vertical component with a zero magnitude along a first line of interest and a second coil partially overlapped with the first coil, where the second coil is to generate a second magnetic field. The example apparatus also includes a sensor to measure a magnitude of the first magnetic field in the first line of interest and a processor to determine an object of interest has crossed the first line of interest based on the magnitude of the first magnetic field measured by the sensor.