From IPL Awards 2018:
Match Awards
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Orange Cap
The Orange Cap will be worn while fielding by the batsman who has scored the most runs in the league (including the Playoffs) during the season to date. It is first awarded once each team has played at least one match and then changes hands when another batsman becomes the highest run scorer in the league to date. The Orange Cap is presented to the batsman at the end of the innings in which he achieves this feat (either at one of the flash interviews or at the post-match presentation). In the circumstance where two or more batsmen have scored the same number of runs during the season to date, the Orange Cap will be retained or awarded, as appropriate, to the batsman (of those who are tied) who has the higher strike rate during the season to date.
Purple Cap
The Purple Cap will be worn while fielding by the bowler who has taken the most wickets in the league (including the Playoffs) during the season to date. It is first awarded once each team has played at least one match and then changes hands when another bowler becomes the highest wicket taker in the league to date. The Purple Cap is presented to the bowler at the end of the innings in which he achieves this feat (either at one of the flash interviews or at the post-match presentation). In the circumstance where two or more bowlers have taken the same number of wickets during the season to date, the Purple Cap will be retained or awarded, as appropriate, to the bowler (of those who are tied) who has the lowest economy rate during the season to date.
So, the answers to the above questions are,
- If more than one player has equal stats (highest runs or wickets), what will they do?
A. In the circumstance where two or more batsmen have scored the same number of runs during the season to date, the Orange Cap will be retained or awarded, as appropriate, to the batsman (of those who are tied) who has the higher strike rate during the season to date. And, when two or more bowlers have taken the same number of wickets during the season to date, the Purple Cap will be retained or awarded, as appropriate, to the bowler (of those who are tied) who has the lowest economy rate during the season to date.
- A player in the field is wearing orange cap for most runs, but in the middle of the innings (it may be first or second) a batsman from the batting side overtakes his runs.
Will he allowed to wear it anymore in that innings?
A. As the Orange Cap is presented to the batsman at the end of the innings in which he achieves this feat (either at one of the flash interviews or at the post-match presentation). A player in the field will wear it till the end of innings.
- Is it permitted to wear these caps while batting?
A. The Orange Cap will be worn while fielding by the batsman who has scored the most runs in the league (including the Playoffs) during the season to date. And, the Purple Cap will be worn while fielding by the bowler who has taken the most wickets in the league (including the Playoffs) during the season to date. So, it is not permitted to wear these caps while batting.