Verb "пробей" means to do powerfull and accurate strike to gate. Verb "бить" it's just a kick.

Бить - просто бить по мячу. Ну и по физиономии, когда сдали нервы. Игрок долго ведет мяч - ему кричат Бей! Не тяни! Есть шанс дать хороший пас другому - Бей! Неплохая возможность пробить по воротам - Бей! Пробить - пробить штрафной, пробить угловой/корнер, пробить пенальти, пробить по воротам, намеренно пробить в аут. Пробить защитника, пробить оборону, пробить полузащиту. Гол!!! Пора пить пиво.

Funnily, two days ago I thought about 'how would I explain this word' in a totally different context (transitive verb used by cahiers: пробить [a purchase] - to make it appear in the receipt). про- means "through". In the sense of piercing [holes], of passing through [gates, forests, tests] and in the sense of 'across the entire time or spatial or any thinkable range'. Also used to form perfective verbs, often denoting completion of actions which could possible be (in)completed to different extent. Also we have "проделать" wich unlike 'сделать' can ony be applied to tricks, operations, acrobatic exercises... but never to obects. Пробить 1. to make a hole with a dull object. 2. In footbal: just a _Perfective_ of бить. to kick the ball. For some reason nobody would ever say 'ударить' in football without specifying: "ударил по мячу"... which makes us think of the ball itslelf, not about performing a kick. It makes some semse when it is used as a transtive verb: про- fits well to the meaning of 'performing' something. That's why i cited проделать. Бей! means just do it, thats, start moving your foot towards the ball:) Any perfective, including "Пробей!" is more likely without an exclamation:/ As a perfective imperative it means: I wish you to complete the action. It makes sense when '...intead of me' is assumed. When its' my wish about the result (I wish it to be done (finally)). When you are making a desicion: to do it or not. In other words. when what I mean is "Now!!!!", i would use IMperfective.

Пробить - to break through (perfective) Schweinsteiger пробил оборону/has broken through defense Бить - to hit (imperfective) Он хорошо бьет по мячу /He hits a ball well. When you hear something like Пробей, Никит! или Бей, Никит - it's almost the same. Just imperative form of Пробить/Бить. Also when we say Пробей - we mean Do it! Kick a goal! When we say Бей - we mean Kick!

пробить - to break through (a barrier) бить - to hit (a ball)