In a collision where a moving soccer ball strikes a stationary soccer ball, the stationary ball will begin to move in the direction of the moving ball. The moving ball will either decelerate or lose some of its velocity, depending on the mass and speed of both balls.
Given that the force of 1.2 kN implies that the moving ball has significant momentum, the most likely outcome is:
The stationary soccer ball will begin moving downfield and the ball that struck it will slow down.
This option correctly reflects the physics of the situation, assuming an elastic or partially elastic collision where momentum is transferred from the moving ball to the stationary ball.