CHICAGO -- Nico Hoerner thought about the question for a moment, but what he experienced last fall kept jumping to the forefront of his mind. The Cubs' rookie was asked for his favorite moment in baseball to date. His mind's eye saw the ivy-covered wall and sea of red-and-blue filling the stands.

"My first game at Wrigley Field," Hoerner said during MLB's Rookie Development Program in Miami last week. "It's a recent memory, but it is probably the biggest high I've had on a baseball field of just pure joy."

It was just the fifth game of Hoerner's career, which was fast-tracked when the Cubs needed a shortstop for the stretch run in September. In a year's time, Hoerner ascended to Wrigley Field from Stanford, and his first at-bat in the Friendly Confines resulted in a two-run homer that had the old ballpark shaking in a romp over the Pirates.

The blast came on the first pitch Hoerner received -- a fitting glimpse into the approach the rookie took in his first taste of the big leagues. The 22-year-old Hoerner, who will come to camp as a candidate for Chicago's second-base job this spring**,** was learning on the fly. Under the circumstances, he did not think being tentative was the right route.

At MLB's annual program -- one also attended by Cubs prospects Robel Garcia, Tyson Miller and Zack Short -- Hoerner said his aggressiveness in the batter's box was intentional. It helped lead to some memorable moments, but it also exposed some things that Hoerner knows he has to work on in order to help the 2020 Cubs as much as possible.

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"I went into it wanting to be aggressive," Hoerner said. "I knew that mistakes would come with that, but I didn't want to be passive about it. And with that came, I didn't control the strike zone -- like, at all. So, that's definitely something I know I can get better at."

One glance at Hoerner's swing rates shows exactly what the rookie is referencing. In 2019, all MLB hitters combined swung 47 percent of the time, while Hoerner had a 57.4 percent swing rate. He offered at pitches outside the zone 48.6 percent of the time, compared to a 31.6 percent MLB rate. His swing rate on pitches in the zone (71.3 percent) was also slightly above the MLB mean (68.5 percent).

And, really, it was a tale of two 10-game samples for Hoerner, who hit .282/.305/.436 overall in his 20 games (82 plate appearances) with the Cubs. The infielder hit .317/.364/.512 in his first 10 games (Sept. 9-18) and then .243/.237/.351 in his final 10 (Sept. 19-29) to close out his season.

Let's look at what changed between the two segments:

SEPT. 9-18

Swings outside zone: 46.2 percent
Swings inside zone: 74.1 percent
Overall swing rate: 57.1 percent
Contact outside zone: 69.1 percent
Contact inside zone: 88.4 percent
Overall contact rate: 78.8 percent
Swinging-strike rate: 12.1 percent
Fastballs seen: 55 percent
Breaking balls seen: 40.3 percent

SEPT. 19-29

Swings outside zone: 51.1 percent
Swings inside zone: 68.4 percent
Overall swing rate: 57.7 percent
Contact outside zone: 78.7 percent
Contact inside zone: 92.3 percent
Overall contact rate: 84.9 percent
Swinging-strike rate: 8.7 percent
Fastballs seen: 62.4 percent
Breaking balls seen: 34.9 percent

The more at-bats that Hoerner racked up, the more pitchers began playing to his aggressiveness at the plate. He saw more fastballs as the month of September wore on and, while his contact rate improved down the stretch, his results declined. There was a more calculated approach to getting Hoerner to chase, and it was effective for opposing arms.

As Hoerner noted, he knew his approach increased the risk of running into mistakes. What he has shown throughout his professional career, however, is that he can adjust quickly, as evidenced by his steady rise through Chicago's farm system en route to the big leagues.

"I have a lot of confidence in my swing itself," Hoerner said. "That's something that will always evolve, and I think the more chances I give myself to hit good pitches, that will take me a long way."

As things currently stand, Hoerner looks like a leading candidate for the vacancy at second base, along with David Bote and others. Cubs president of baseball operations Theo Epstein has reiterated that the team has not made a decision about whether Hoerner's development might be better served with more at-bats at Triple-A Iowa. That internal debate will take place throughout the spring.

"Second base is an area where we definitely are out there looking," Epstein said at the Winter Meetings. "But we have a number of good players on our roster at second. We've said that we're not closing any doors on Nico. We're open-minded, and we'll use Spring Training and put our heads together on what we think is best for him and the best for the team."