CINCINNATI -- The first big decisions of the Hot Stove season are looming this weekend for all Major League clubs. But extra attention will be on a pair of Reds stars -- right fielder Nick Castellanos and Trevor Bauer -- and decisions that could determine whether they return to Cincinnati.

By 11:59 p.m. ET Friday, Castellanos must decide whether he will opt out of the four-year, $64 million contract that he signed in January. By Sunday at 5 p.m., teams must extend a qualifying offer to their free agents. Bauer is the only one of the four Reds free agents expected to receive one. Players then have 10 days after Sunday’s deadline to accept the offer, which is for $18.9 million.

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For the 28-year-old Castellanos, there are several reasons why he should not opt out and become a free agent:

• His 2020 performance: Castellano’s first season in Cincinnati was a mixed bag. Despite a scorching start in the first few weeks, the season was lackluster overall. His 102 OPS+ was a dip from 2019. While he had a 122 OPS+ overall in '19, his 153 OPS+ following a Trade Deadline deal from the Tigers to the Cubs was what excited the market last winter. Castellanos did finish '20 with 14 home runs while playing in all 60 regular-season games, but his final slash line was .225/.298/.486. And despite much attention to improving defensively, he was worth minus-5 Outs Above Average, per Statcast -- tied for the worst among outfielders and the same figure he produced in ’19

• Economics: The pandemic and its subsequent impact have made for murky financial outlooks. Teams took losses by not having fans in the stands, which means there will likely be fewer bidders to sign Castellanos. With three years and $48 million left on his deal with the Reds, it could be difficult to do better on the open market.

• There is a second opt-out clause after the 2021 season for Castellanos. Improved performance and a stronger economy would enable him to take another shot at cashing in.

Here is one reason Castellanos could opt out this week: His agent. Clients of Scott Boras signed over $1 billion worth of free agent contracts last winter. Throughout his career, Boras has often found ways to create a market demand for players where one wasn’t thought to exist. If anybody could figure out how to get Castellanos more money from a club, it would be Boras.

If Castellanos were to opt out, the Reds do have in-house replacement options with Jesse Winker or Aristides Aquino. But the club would still likely need another impact bat somewhere in the lineup. Free-agent right fielders include Ryan Braun, former Red Jay Bruce and the biggest prize of all, George Springer.

As for Bauer, the No. 1 starting pitcher on the market and the leading candidate for the National League Cy Young Award, the decision is almost a formality for both him and the club.

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The Reds are certain to offer Bauer the $18.9 million for one year and he’s just about as certain to decline. The 29-year-old is a first-time free agent and wants to explore the market.

Bauer was 5-4 with an NL-best 1.73 ERA, 276 ERA+ and 100 strikeouts in 11 starts over 73 innings. In Game 1 of the NL Wild Card Series, a 1-0 Reds loss to Atlanta in 13 innings, he pitched 7 2/3 scoreless innings with 12 strikeouts in a no-decision.

The other Reds free agents are starting pitcher Anthony DeSclafani, shortstop Freddy Galvis and reliever Tyler Thornburg.

If Castellanos were to opt out of his contract and become a free agent, he would likely join Bauer in receiving a qualifying offer. If either or both players sign elsewhere, the Reds would receive Draft-pick compensation.

Keep this in mind: There have been 90 players who have received a qualifying offer since it was implemented in 2012, and only eight have ever accepted.