Power Play - This is a rule involving ODI field restrictions introduced in 2006. Previously during the first 15 overs only 2 fielders were allowed outside the 30 yard circle. This resulted in batsman taking many risks in these first 15 overs, making this part of the match very interesting but resulting in the middle part of the match being dull.
Under the new rule, the first 10 overs allow only two fielders outside the 30-yard circle after which there are two blocks of five overs each (known as Powerplay fives) in which the same restrictions apply. These blocks can be used by the captain at any stage of the match. If not, then they will be automatically enforced in the 41st and 46th over. The captain of the fielding side can use this rule to force a team to take risks at various stages of the match where there will be a good opportunity to pick up wickets.
Another ploy involving the fielders is the field setting for batsmen according to their strengths and weaknesses. The bowler then bowls according to this setting forcing the batsman to take chances on his weaker side, resulting in him being caught out or so on.