April 3 (Reuters) - Essex all-rounder Noah Thain became the first ever injury substitute in county cricket ​in England on Friday when he ‌replaced captain Tom Westley, who broke a finger while batting against Hampshire in Southampton.

The England and ​Wales Cricket Board (ECB) debuted a season-long trial ​earlier this week, allowing fully participating, ⁠like-for-like replacements in the case of injuries, ​illness or significant life events like the ​birth of a child or the serious illness of a family member.

Injured players could be replaced by ​a substitute fielder under existing rules, ​but the ECB allowed them to participate fully after ‌the ⁠International Cricket Council (ICC) asked member boards to experiment with injury substitutes in domestic cricket.

Similar rules have been tried out in the ​domestic first-class ​competitions of ⁠Australia, India and South Africa.

The substitutions must be approved by the ​match referee and once replaced, ​a ⁠player cannot return to the game.

As a like-for-like replacement for Westley, who is primarily a ⁠batter, ​Thain will be allowed ​to bat but cannot bowl in this match.

Reporting by ​Chiranjit Ojha in Bengaluru, editing by Pritha Sarkar