Saracens have signed Scotland second-row Jim Hamilton and Argentina tighthead Juan Figallo from Montpellier.
Former Gloucester lock Hamilton, famed for his robust and aggressive play, is a like-for-like replacement for skipper Steve Borthwick who plays his last game for the club in this weekend's Aviva Premiership final.
The capture of Figallo is a major coup for the Heineken Cup finalists - the Pumas star is rated as one of the best tightheads in world rugby.
Director of rugby Mark McCall said: "Last year we identified a handful of players who we felt would improve what is now a stable, successful and developing squad.
"After long and detailed negotiations, we are pleased to have finally secured each of our targets.
"Juan Figallo was ranked as the world's number one tighthead prop last year and, aged only 26, will prove a massively significant signing.
"He has almost completed rehab following a neck injury and will be ready for the start of the new season.
"Jim Hamilton is one of the most respected lock forwards in the game, a big man with a big presence on and off the field. He was courted by several leading European clubs, and we are delighted he has chosen to join Saracens."
Sarries have also signed England Sevens specialist Mike Ellery.
McCall said: "Mike Ellery is a tall, strong man with both skill and speed. He has been making headlines on the Sevens circuit, and we are looking forward to helping him realise his full potential in the 15-man game."
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