Nemani Nadolo and Dan Cole have signed new deals at Leicester Tigers, who have also brought in Scotland prop Darryl Marfo and recruited Francois van Wyk from Northampton for next season.
Fiji international Nadolo, 33, joined last summer while England prop Cole, 33, has played 253 games for Tigers.
Van Wyk, 29, has spent the past four seasons with Saints, while Marfo, 30, has signed a short-term deal.
Springbok back rower Marco van Staden, 25, has also signed for next season.
A quartet of new signings is completed by van Staden's compatriot Eli Snyman, a 24-year-old lock who will link up with Tigers after finishing the season with Benetton in Italy.
In addition to Nadalo and Cole, four other Leicester players - including Jasper Wiese - have also committed to new deals.
Tigers have agreed extensions, of undisclosed lengths, with Wiese, 25, England Under-18 loose-head prop James Whitcombe, 20, versatile back Dan Kelly, 19, and forward Ollie Chessum, 20.
Leicester head coach Steve Borthwick was delighted with Tigers' several announcements on Monday, particularly the extensions agreed with Nadolo and Cole.
He said: "Nemani is an experienced, world-class winger who has shown what he is capable of in both attack and defence in his short time at the club so far last season and in the opening weeks of the current campaign.
"His commitment to what we are building at Leicester Tigers has been very impressive and I have enjoyed working with him so far and look forward to continuing that in the future.
"Dan's passion for the club and his commitment for a decade and a half is unrivalled.
"He continues to set the standard every day with his work ethic and professionalism. Dan is a smart, tough and aggressive player who will continue to play an important role."
Loose-head prop Marfo has been without a club since a short spell with Welsh Pro14 side Ospreys last season.
He began his professional career at Harlequins, and has also spent time at London Welsh, Bath and Edinburgh, where he made his Test debut for Scotland.
Van Wyk made his Currie Cup debut for Western Province in 2013 before moving to Australia to play for Super Rugby side Western Force in 2014.
"We are excited to have someone of his experience, ability and character," Borthwick said. "Francois has played top-flight rugby in both hemispheres and will add vital depth to our front row ranks."
Van Staden, meanwhile, will join Tigers from Super Rugby side The Bulls.
"He is a tough, hard-working, competitive player who we are confident will add to what we are building here at Leicester Tigers," Borthwick added.