Virtually all position is really important in a match in order to win a match but most times, I do think some positions are important that some, why? Take for instance, playing a match without a striker or strong attacking players, it would really be difficult for a team to secure a winning, this may be correct to some cases and also wrong in other cases.
Let me explain it this way, now for a team to win a match it does naturally depends on the striker, why? Because most teams perform and score more goals when their midfield are active on the fields, while others could perform best through the influence of the two back players, the left and right back (defenders), which implies that it is the wing at the back that drives the ball forward to the two attacking wings or better still the two wings does more of long passes to the forwards, so they get a goal from it.
Now back to the Question, I don’t think they is any position that is more important that the other, because all positions in a team are important in their respective roles and if one position is missing it would really affect the club, however, based on scoring goals, having possession against the other team, defending, some players could be important than the others, because deficiency of a particular role be it the attack, defense or midfield would affect the performance of that team either in the scoring ways, defending and attacking. So we can only say a certain player is important in a particular match only if his attention is needed more to win the match, like for instance having a team with very good attackers ready to score but they are having problems with a particular player to create that chances for they, it is then we can say a No 10 player is needed to fill that position and to create that final pass or better still a No 8 to create a pass to score a goal, also having a team that the midfield easily get penetrated from the the opponents midfield, we can now presume that the defensive midfielder is more needed in the match in order to make the midfield a little stronger, but aside this scenarios and other important ones that would require the performance of a particular player more than other players, I don’t think a player is more important than other players in a match only in rare cases.
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