The slip cordon in cricket is a collective term for a group of fielders standing on the off-side beside the wicket-keeper. More often than not, these fielders are top order batters.
Each slip fielder is named based on his or her position from the wicket-keeper. The one immediately beside the keeper is the first slip, then the second slip, and so on. The number of slip fielders depends on the pace of the bowler and the line and length which the bowler is planning to bowl at. Usually, there are three slips for a fast bowler. This is commonly seen in the initial overs when the new ball swings. Bowlers who opt for the off theory, target the area slightly outside the off stump, aiming to catch the edge of the batter’s bat. The bowl thus flies to the slip fielders.
A spinner will have no more than one slip on the off-side. However, they can have a leg slip, which is a variant of the slip fielder, but on the leg side. The spin inculcated on the bowl when miscued, can send the ball in a wayward direction which is one of the reasons why a leg slip is placed.
It was in 1977, when all nine fielders were positioned as slips. This happened in a test match between Australia and New Zealand. The second instance of such a scene was seen in 2000 in a One Day International match between Australia and Zimbabwe.