Sentence:  A smart defensive player knows when to <WSD>backcheck</WSD> the puck carrier and when to <WSD>backcheck</WSD> to cover an open player. / Hockey has no greater test of your heart and intensity than your willingness to <WSD>backcheck</WSD>, particularly at the end of a sustained attack when the other team has suddenly come up with the puck and you are feeling exhausted. 
Meaning of the word marked with <WSD> tags:  To engage in checking while skating toward or near one's own goal.