Heading into the 2020 season, first base had been one of the most stacked positions on the Nationals' roster. It would be up to manager Dave Martinez to juggle innings between Howie Kendrick, Eric Thames and Ryan Zimmerman on the field.

Quickly, that veteran trio is down to one.

Zimmerman elected not to play this year, and Kendrick has not yet been cleared to participate in Summer Camp workouts with Opening Day less than two weeks away. That leaves Thames in line to man the position more often than originally anticipated.

“Staying healthy, whether it’s an actual injury or getting sick, that’s the No. 1 priority,” Thames said on Saturday. “It is definitely different right now at first base.”

Thames began his big league career in the outfield. When he traveled overseas to play in the Korea Baseball Organization, he transitioned to first base, logging 2,844 innings with a .993 fielding percentage in three seasons.

“It was a lot of reps in Korea -- hours and hours and hours of ground balls,” Thames said. “Over here, it’s a little different, but over there, I was learning the position, learning what to do. That definitely helped me a lot.”

Thames remained at first base when he returned to MLB to play for the Brewers from 2017-19. During that time, he recorded a .993 fielding percentage over 1,855 1/3 innings at first, playing 242 games there (including 219 starts).

This past winter, Thames signed a deal to join the Nationals for his sixth Major League season.

“He seems to fit in really well, from what I’m noticing,” Martinez said. “Guys love him. He jumps right in, he’s a good teammate, he wants to do everything he can to help us win ballgames.”

The Nationals have looked forward to seeing what Thames can do at the plate, making him a candidate to play designated hitter, which will be in the National League for the first time this season. Martinez said having Thames in the lineup is going to be “tremendous,” especially against right-handers. Last season, Thames hit 23 home runs with a .529 slugging percentage against righties. Now, Thames’ to-do list is much more extensive than just going yard.

“He’s got tremendous power, as we all know,” Martinez said. “I know he’s working diligently with [bench coach Tim Bogar] and [third-base coach] Chip [Hale] over at first base. He wants to be a really good defender. He’s showing signs where he can stand out there and play a good first base.”

Thames noted Washington’s coaching staff is “adamant about defense.” During Summer Camp, he’s been answering the call.

“They’ve been all over me about getting work in and extra fungos and everything,” Thames said. “In baseball, it could be the ninth inning, a big play to [shortstop] Trea [Turner] up the middle, he spins and throws it on an in-between hop, you’ve got to dig it.

“I’m busting my butt over here.”