GOODYEAR, Ariz. -- The last time a change to his hitting approach was installed, Reds center fielder Nick Senzel wasn't ready. It was in the midst of Senzel's 2019 rookie season and then-assistant hitting coach Donnie Ecker had him open his batting stance, stand tall in the box with a wider posture and add a leg kick.

Bottom line: the changes did not take.

“When they first came to me with this swing adjustment, it was just so much," Senzel said. "It was my first year in the big leagues, I was trying to fit in and I was trying to establish myself. It was a lot on me, mentally. I wasn’t mature enough as a person to kind of take that on and run with it, so it was a little difficult. I’m in a better position to take that on. And to be quite frank, I need to do it.”

Senzel would return to his original approach, but he eventually saw his power dwindle in 2022. While batting .231 with a .601 OPS, he had five home runs and an average exit velocity of 87.2 mph -- only in the 16th percentile among Major League hitters.

It's become a crucial period for the 27-year-old Senzel to finally establish himself in Cincinnati's 2023 lineup.

“Listen, it’s no secret that I would like to play better," Senzel said. "I think a lot of things have happened that deterred that, a lot of it self-inflicted, injuries, whatever the case may be. I love this game and I want to play well. I’m in a good spot, mind and body, to be able to work and dedicate and do the things I need to do to have a great year.”

Late last season, assistant hitting coach Joel McKeithan suggested a new adjustment. Similar to 2019, Senzel stood tall and hovered his left foot off the ground as the pitch arrived. But, he would be less wide in his stance and more balanced.

"It allows him to move in rhythm to the ball and be a little more athletic in recognizing and adjusting to pitches. He should be able to get his good swing off on anything," said McKeithan, who was promoted to hitting coach in the offseason. “It was like, ‘OK, what didn’t you like about trying this the first time? What are the foundational things you need to have in your swing?’ The main thing was just finding balance.”

Five of Senzel's top seven exit velocities came in September, including a season-high 109.5 mph on Sept. 4 vs. the Rockies and 107.3 mph on Sept. 13 vs. Pittsburgh.

However, both instances resulted in outs.

"You saw his ability to adjust and drive the ball," McKeithan said. "The numbers weren’t necessarily there in terms of results, but in terms of exit velo and staying in the middle of the field and driving the ball, it seems to have helped.”

Unfortunately for Senzel, he didn't get to build on those results. He missed the final 14 games of the 2022 season when he fractured his big left toe in a wall collision on Sept. 20 vs. the Red Sox.

The healing went poorly and Senzel needed surgery. He wore a boot and used a scooter to get around most of the offseason and only resumed baseball activity a couple of weeks ago. He still came to camp in good physical shape, but now, he needs to get into baseball shape. That has him behind others in getting ready for the season. He still hasn't hit against pitchers in camp and isn't scheduled to play in the early Cactus League games.

That puts Opening Day in doubt.

“It’s going to be close," Reds manager David Bell said Thursday.

During the offseason, Bell noted that Senzel would have to earn his spot -- especially with other outfielders in camp. Senzel could also see time at other positions, including third base.

"If he’s healthy, he’s going to play," Bell said.

Injuries have dogged Senzel for much of his four-year career. But he played a career-high 110 games last season and felt like he could resume his late 2022 momentum. He also thinks that he and McKeithan clicked in ways that he couldn't with others.

“We have a great relationship, a great working relationship. I trust what he has to say," Senzel said. "I think now, I’m more mature. It’s time now to really do some tough things, some challenging things, to push myself into a position where I can get the most out of my abilities."