The ball is a hard leather-seamed spheroid, with a circumference of 22.9 centimetres (9.0 in). The ball has a "seam": six rows of stitches attaching the leather shell of the ball to the string and cork interior. The seam on a new ball is prominent and helps the bowler propel it in a less predictable manner. During matches, the quality of the ball deteriorates to a point where it is no longer usable; during the course of this deterioration, its behaviour in flight will change and can influence the outcome of the match. Players will, therefore, attempt to modify the ball's behaviour by modifying its physical properties. Polishing the ball and wetting it with sweat or saliva is legal, even when the polishing is deliberately done on one side only to increase the ball's swing through the air, but the acts of rubbing other substances into the ball, scratching the surface or picking at the seam are illegal ball tampering.
India has had six regular Test captains since Mohammad Azharuddin took charge in 1989. Azharuddin led the team in 47 Test matches from 1989–90 to 1998–99, winning 14, and in 174 ODIs, winning 90. He was followed by Sachin Tendulkar, who captained the team in 25 Test matches and 73 ODIs in the late 1990s; Tendulkar was relatively unsuccessful as a captain, winning only 4 Test matches and 23 ODIs. He was replaced as ODI captain by Ajay Jadeja and then by Sourav Ganguly.
In the approximate centre of the field is a rectangular pitch (see image, below) on which a wooden target called a wicket is sited at each end; the wickets are placed 22 yards (20 m) apart. The pitch is a flat surface 3 metres (9.8 ft) wide, with very short grass that tends to be worn away as the game progresses (cricket can also be played on artificial surfaces, notably matting). Each wicket is made of three wooden stumps topped by two bails.