Matt Prior has announced his departure from the Sharks to Leeds, which has triggered Trent Merrin's exit from the Super League club to return to the NRL with his junior club St George Illawarra.
In announcing Merrin's homecoming, the Dragons also released forward Luciano Leilua, who has joined the Wests Tigers on a three-year deal.
Prior's signature is a massive boost for Leeds - the 32-year-old prop, who has played more than 250 games in the NRL and represented NSW in an Origin match in 2018, has inked a two-year deal.
A premiership winner in 2010 with the Dragons and 2016 with the Sharks, Prior will link with his former Cronulla teammate Ava Seumanufagai at the Rhinos.
"I know that Leeds Rhinos have a fantastic history but have had some tough times in recent years," Prior said.
"Hopefully I can play my part in lifting the clubs fortunes and get us back to challenging for silverware again. I know Ava Seumanufagai and Adam Cuthbertson well so it will be good to catch up with those guys and I am sure everyone will make me feel at home.
"I nearly signed for the Rhinos a couple of years ago but we didn’t get the deal done so this is something I have always had in my mind.
"It is an exciting time to be moving to Super League with players like Sonny Bill Williams, Gareth Widdop and George Burgess coming into an unforgiving competition and I can’t wait to get involved with the Rhinos boys in training."
Merrin was also part of St George Illawarra's 2010 title team and has agreed to a two-year contract with his former club after Leeds released him on "compassionate grounds".
Merrin debuted for the Red V in 2009 and spent seven seasons with the club where he amassed 133 NRL games.
The Shellharbour Sharks junior spent a further three seasons at the Penrith Panthers before venturing abroad last year to play for Leeds.
The 30-year-old has played 13 Origins for NSW and seven Tests for Australia across his 11-year first grade career.
"Trent could've jumped like a kangaroo all the way back to Australia he's that excited to come back to the Dragons," Dragons director of pathways Ian Millward said.
"Trent has indicated to the club several times over the past 12 months that he'd love to come home; an opportunity for this has since come up after the club granted Luciano his requested release.
"Luciano indicated he wouldn't be renewing his contract with the Dragons beyond the 2020 season. As a result we'll be able to do a multiple things as far as overall recruitment is concerned with Luciano's money.
"Trent brings plenty of experience to the Dragons' forward pack and is someone who is really passionate and can't wait to put the Red V back on."
Tigers coach Michael Maguire believes he can get the best out of Leilua.
"I’m very pleased we’ve been able to secure a player with Luciano’s talent and potential for the future," Maguire said.
"He offers another dimension to our forward pack and gives us an added edge with his ball-playing and creativity.
"With more experience and time, I can see Luciano developing into a really strong player for this club and we’re all excited to see him take those next steps in his career here."