Now that the new year is here, that means pitchers and catchers aren't far off from reporting. To help pass the time until Opening Day (and hopefully sate appetites), we intend to spend the rest of the winter profiling the offseason's biggest additions and figuring out what makes them so effective. That process began last month with Gerrit Cole and Anthony Rendon. Today, let's focus on the winter's one big-time free agent to remain in place: Stephen Strasburg.

Here are four reasons the Nationals decided to pay up to keep Strasburg around.

1. Elite changeup

We may as well start with one of the best pitches in baseball: Strasburg's changeup. It's the top offering in his arsenal, and it might be the most fierce cambio in the game -- though Luis Castillo, among others, would contend otherwise. 

Strasburg throws his changeup using a circle group, imparting a spin on the pitch that causes it to fade and run toward the arm side. Take a look:

In addition to more than passing the eye test, the changeup also grades well statistically. Opponents have hit no better than .171 against the pitch in any season, per Baseball Savant. They've also whiffed on at least 40 percent of their swings taken on it. Those are wild numbers.

2. Deep arsenal

While Strasburg's changeup is the proverbial breadwinner of his repertoire, it's not his only above-average pitch. Indeed, one talent evaluator told CBS Sports he grades all three of Strasburg's main pitches -- his changeup, fastball, and curveball -- as plus or better offerings.

Generally, a pitcher is doing well to have two plus or better pitches -- having three is part of the separator between a front-of-the-line starter and a mid-rotation type. Factor in Strasburg's command -- a nearly metaphysical trait that describes a pitcher's ability to locate and, well, command the pitch -- and there's a reason he's been one of the game's best when healthy.

3. Adaptability

Another reason why Strasburg tends to dominate? His adaptability. He doesn't throw as hard as he used to, with his fastball clocking in at 93.9 mph last season, but he's shown an aptitude for making tweaks -- like, say, using said fastball less often in favor of his curveball.

Strasburg's feel for making adjustments came in handy during the World Series. Not only did he alter his mechanics to avoid tipping his pitches in Game 6, but he also spammed the Houston Astros with curveballs, throwing more than 40 percent. Here's what we wrote at the time:

In some respect, it's fitting that Strasburg relied so heavily on that pitch in what's presumed to be his final masterpiece of the year. He set a new career-high in curveball usage during the regular season, delivering the pitch more than 30 percent of the time. What's more is that during the regular season, he used it 40-plus times in five separate outings. Entering the 2019 season, he'd never crossed that threshold, according to data from Statcast.

Baseball is a game where long-term success is almost always dictated by adjustments -- be it to the opponent or to decaying physical abilities. There's a chance Strasburg's physical woes catch up to him, but he seems positioned to age well so far as the mental parts of the game go.

4. Legacy

Let's face it, part of the Nationals' motivation for keeping Strasburg was based on what he means to the franchise. It's not a stretch to say he was the single most important member of their club throughout October and he was named World Series MVP. 

So much of baseball management these days is about stripping the emotion from the decision-making process. But operating in a feelings vacuum is perhaps as shortsighted as making decisions based on what tugs at the heartstrings. Part of the business is attracting fans, and part of attracting fans is permitting them to establish meaningful emotional connections to the players on the field. 

Obviously the Nationals have let their share of fan favorites leave -- Anthony Rendon and Bryce Harper have both exited the past two winters -- but that, as well as Strasburg's October, gave them even more incentive to pony up. Expect to see a lot of Strasburg jerseys around Nationals Park for years to come -- as well as a lot more Nationals wins in games Strasburg starts.