O'Reilly, 32, will make $4.5 million against the salary cap on a four-year term. He played last season with the St. Louis Blues and the Toronto Maple Leafs, who acquired him at the trade deadline. O'Reilly became an unrestricted free agent Saturday, and Nashville snatched him up.
The Predators and new general manager Barry Trotz have dramatically revamped their center position in the offseason, trading Ryan Johansen to the Colorado Avalanche and buying out the last three years of center Matt Duchene's contract.
Nashville also signed defenseman Luke Schenn of Toronto on Saturday on a three-year, $8.25 million deal.
O'Reilly finished up a seven-year contract last season. The deal carried an average annual value of $7.5 million, and the Blues rid themselves of it at the trading deadline, shipping their captain to the Maple Leafs.
O'Reilly's start with Toronto was up-and-down as he scored a hat trick not long after the deal, in a win over the Sabres, but on March 3, the club announced he had a broken finger. The 32-year-old center then went on long-term injured reserve, saving Toronto some salary cap room before the playoffs began April 17.
O'Reilly was one of six new players former Toronto general manager Kyle Dubas brought in before the trade deadline in an effort to make the team more competitive. A Stanley Cup winner and playoff MVP in 2019, O'Reilly won 84.4% of his faceoffs with the Maple Leafs before being deactivated.
The veteran helped Toronto get past the first round for the first time since 2004, leading the Maple Leafs past the Tampa Bay Lightning in six games. But Toronto was quickly scurried out of the postseason in Round 2, when the Florida Panthers eliminated the Maple Leafs in five games.
In 2019, O'Reilly was instrumental in St. Louis' worst-to-first season. The Blues won a Game 7 on the road to eliminate the Boston Bruins and secure the club's first Stanley Cup, with O'Reilly winning the Conn Smythe Trophy as playoff MVP.