Jaiswal had made the trip to London as a stand-by player along with Mukesh, after Gaikwad, who was part of the original list of back-ups, withdrew to get married. While Jaiswal and Mukesh are uncapped, Gaikwad has played ten limited-overs internationals; his most-recent an ODI against South Africa in October last year.
Gaikwad, who plays for Maharashtra, has a first-class average of 42.19 from 28 games with six centuries, and his technique has impressed the selectors and team management who have been looking to bring him into the Test team for a while now.
Jaiswal has been prolific for Mumbai and has a first-class average of 80.21 in 26 innings. In his most recent first-class game - the Irani Cup - he made 213 and 144 for Rest of India against Madhya Pradesh. That aggregate of 357 is the most for any batter in an Irani Cup game. Jaiswal has the ability to not just open but also bat at No. 3 if required.
Mukesh is a workhorse who plays for Bengal. The 30-year-old is a line-and-length fast bowler who has built an impressive body of work in domestic cricket. He was key to Bengal making two Ranji Trophy finals in the last three seasons and has been on the Test radar for a while, having featured in every India A tour over the past two seasons. He has 149 wickets in 39 first-class games.
India open their tour of the West Indies with the first Test in Dominica from July 12. The second Test begins on July 20 at Queen's Park Oval in Port-of-Spain. They won their previous Test series in the Caribbean 2-0 in 2019.
India's Test squad: Rohit Sharma (capt), Shubman Gill, Virat Kohli, Ajinkya Rahane (vc), Ruturaj Gaikwad, Yashasvi Jaiswal, KS Bharat (wk), R Ashwin, Ravindra Jadeja, Axar Patel, Shardul Thakur, Mohammed Siraj, Mukesh Kumar, Jaydev Unadkat, Ishan Kishan (wk), Navdeep Saini