CINCINNATI -- The Reds showed just how serious they were about upgrading their lineup this offseason on Monday. On Thursday, Cincinnati announced it signed free agent Mike Moustakas to a four-year, $64 million contract. It's the largest contract ever given to a free agent in the franchise’s history.

Although a natural third baseman, Moustakas is expected to fill the vacancy at second base. The Reds already have Eugenio Suárez installed at third base and under a long-term contract.

"We welcome Mike and his family to the organization," president of baseball operations Dick Williams said. "We know he will have an immediate and significant impact on our team and is going to help us in our relentless pursuit of championships."

Moustakas, 31, batted .254/.329/.516 last season with 35 home runs and 87 RBIs in 143 games for the Brewers and made the National League All-Star squad. He has averaged 34 homers with an .817 OPS over the past three seasons.

A three-time All-Star and left-handed hitter, Moustakas languished on the open market each of the previous two winters and had to settle for one-year contracts – first with the Royals and then for Milwaukee.

Moustakas spent the first six seasons of his career as a star third baseman for the Royals and played in the 2014 and ’15 World Series, including winning the title in 2015. He was traded from Kansas City to Milwaukee on July 27, 2018.

The Brewers used Moustakas at second base in 47 games during this past season, including 40 starts. He eventually was moved back to third base.

Heading into this offseason, the Reds placed a premium on adding offense. Cincinnati ranked 12th in the NL in hitting and runs scored, while going 75-87. Although the Reds set a new club record with 227 home runs, they scored 701 runs -- just five more over the previous year. They made an attempt to sign free-agent catcher Yasmani Grandal, but he signed a four-year, $73 million contract with the White Sox.

With Suárez at third base, Joey Votto at first base and Freddy Galvis a leading contender for shortstop, the most unsettled spot in the infield was at second base. Last season, José Peraza, Derek Dietrich, Scooter Gennett and Josh Van Meter were among the players stationed there. Peraza was non-tendered ahead of Monday’s deadline, making him a free agent. Dietrich was taken off the 40-man roster last month when he was sent outright to Triple-A Louisville, while Gennett – a star for the club in 2017-18 -- was traded to the Giants on July 31.

Adding Moustakas would also seem to cement Nick Senzel as the Reds’ center fielder long term. Senzel, a second baseman in the Minors while he was the organization’s top prospect, converted to center field ahead of the 2019 season and made his Major League debut in May.

Now the Reds have positional stability again at second base with a veteran run-producer like Moustakas.