The seasoned New Zealand bowler Boult made his IPL debut in 2014 and played for DC in the 2018 and 2019 season. He has 38 IPL wickets from 33 games.
Rahane, who has been trying to get back into India's limited overs set up, established his T20 credentials as an opener after moving to Royals from Mumbai Indians in 2011
Sunrisers Hyderabad has released Deepak Hooda, Martin Guptill, Ricky Bhui, Shakib Al Hasan, Yusuf Pathan.
The other names doing the rounds are Evin Lewis, Barinder Sran, Jayant Yadav, Mitchell McClenaghan and Jason Behrendorff
Rahane returns to lead Royals for the game against Delhi Capitals on Saturday after Smith replaced him as captain in the middle of the season following the team's disappointing run
Royals signed off their home leg on a winning note as they defeated Sunrisers Hyderabad (SRH) by seven wickets on Saturday night
Stokes said there was no point in looking back and focus on the upcoming games because if they lose the next two, bouncing back could be beyond Royals' reach
The decision to go pink came after the huge response from the fans last season and the deep routed link between the colour and the state of Rajasthan.