It used to be that doctors recommended long periods of rest after an injury like yours. But they soon found that extended rest led to other problems, such as stiff joints and weak muscles.
Researchers suggest complete rest of the injured leg for 24 to 48 hours after a contusion. This seems to be the right amount of time to prevent extra blood from forming within the muscle. After a day or two, you should be able to start light movement such as walking, as pain permits. Avoid aggressive stretching, which may cause the formation of bone tissue within the thigh muscle, a condition called myositis ossificans.
Once you have better range of movement in your leg, you should be able to return to full activity. Talk to a doctor or sports trainer about how soon it’s safe to return to soccer, given the severity of your injury.