CINCINNATI -- Just as the Reds are trying to finalize their largest free-agent contract with veteran slugger Mike Moustakas this week, another one could follow that’s even bigger.

A source told MLB.com on Tuesday that Cincinnati is one of the teams in close pursuit of free-agent starting pitcher Zack Wheeler. Wheeler and his agent have told clubs they would prefer to get a contract done ahead of next week’s Winter Meetings in San Diego.

Ken Rosenthal of MLB Network and The Athletic reported on Tuesday that Wheeler already has one offer that is worth at least $100 million. He also listed the White Sox, Rangers, Twins and Blue Jays among other interested teams.

On Monday, a source told MLB.com that the Reds and Moustakas agreed to terms on a four-year, $64 million deal. Cincinnati has made upgrading the offense its top priority, but president of baseball operations Dick Williams has also expressed interest in adding pitchers. Williams noted in October that his budget -- which was a club-record $126 million in 2019 -- has been increased by ownership to make roster upgrades.

Wheeler, 29, overcame right elbow surgery that cost him the entire 2015 and ’16 seasons and part of ’17 as well. Over his last two seasons for the Mets, he is 23-15 with a 3.65 ERA, 3.37 FIP and 8.9 K/9 IP. Wheeler set a career high with 195 1/3 innings pitched last season while going 11-8 with 3.96 ERA in 31 starts.

The Reds have a more pressing need for bullpen arms than starters. The top four in their rotation are Luis Castillo, Sonny Gray, Trevor Bauer and Anthony DeSclafani. Both Bauer and DeSclafani are in their final years of club control and can become free agents following the 2020 season.

Because Wheeler was one of 10 free agents to receive the $17.8 million qualifying offer from his team, it would cost a new team Draft-pick compensation to sign him.