NORTH PORT, Fla. -- Austin Riley spent the offseason making mechanical adjustments aimed toward creating more balance at the plate. But more importantly, the Braves third baseman must now prove he can gain the plate discipline necessary to avoid an extension of last year’s sudden decline.

“I knew the failures were going to be there, and they were longer than what I wanted, but I did have some success, and I know what I can do up here,” Riley said. “That’s been a big positive on me mentally because this game is so hard on you mentally. What I did during the offseason, I know it’s going to carry over, and I think there will be some upside this year.”

Riley got to flip the page when he made his Grapefruit League season debut during a 5-1 loss to the Tigers on Sunday afternoon at CoolToday Park. He lined out to center in the first inning and popped out to center in his only other plate appearance. His mission now is to continue make an impression as he battles Johan Camargo to replace Josh Donaldson as the Braves’ third baseman.

“He feels good, and I know he worked hard during the offseason,” Braves manager Brian Snitker said.

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Recognizing the need to make adjustments, Riley went to Dallas in December to work with Braves Minor League hitting coordinator Mike Brumley. Their need to focus on balance was necessitated by Riley’s tendency to put too much of his weight on the toes of his back foot. This too often led him to essentially jump at pitches and slide his feet while swinging.

As last summer progressed, former Braves catcher Brian McCann stressed the need for Riley to keep his weight evenly distributed through his back foot while swinging. But this was an adjustment easier made while not being stressed with the need to produce. The changes Brumley helped along finally started to feel comfortable by the end of January.

“Past springs, I feel like I’ve come in searching for something and trying to figure out my swing with that slide or something with my elbow,” Riley said. “Now, I can work on my approach and work on seeing that strike or ball. That allows me to make that adjustment quicker to seeing live pitching.”

Riley’s tremendous potential was displayed when he hit 14 homers (one homer every 11.5 at-bats) and produced a .930 OPS through his first 42 career games last year. Still, there were signs of potential trouble as he had a 31.8 percent strikeout rate and walked eight times during this stretch of 174 plate appearances.

After surging through the early weeks of his career, Riley constructed a meager .495 OPS over the 38 games totaled over the rest of the season. He struck out 42.3 percent of the time and drew just six unintentional walks over 123 plate appearances.

Here’s a Statcast breakdown that indicates how he fared against four-seamers and sliders during these two spans:

First 42 games
Vs. four-seamers: 28.3 percent of pitches seen, .288 batting average (15-for-52), .654 SLG, 32.7 whiff rate (35 of 107)
Vs. sliders: 24.3 pct. pitches seen, .188 (6-for-32) BA, .406 SLG, 48.0 whiff rate (48 of 100)

Other 38 games
Vs. four-seamers: 31.8 pct. pitches seen, .108 BA (4-for-37), .216 SLG, 37.1 whiff rate (33 of 89)
Vs. sliders: 23.7 pct. pitches seen, .083 BA (2-for-24), .208 SLG, 53.3 whiff rate (32 of 60)

“People say I can’t hit the slider, can’t hit the slider, can’t hit the slider,” Riley said. “I can hit them when they’re in the zone. I proved that. I hit a couple of those balls out. It’s recognizing which are strikes and balls and being able to lay off those outside the zone, and then to be able to hit the fastball whenever I get it.

“I felt like later in the season, I was more focused on trying not to swing at that slider, so I wasn’t catching up to the fastball. I think the biggest thing is staying on that fastball and being able to recognize that slider. I think this swing I’ve made is going to allow me to do that.”