Adam Eaton is back on the disabled list. (Alex Brandon/AP)

Electing to take a careful approach with their left fielder, the Washington Nationals officially placed Adam Eaton on the 10-day disabled list with a bone bruise in his left ankle on Wednesday morning. Moises Sierra was called up from Class AAA Syracuse to replace him on the active roster. To make room for Sierra on the 40-man roster, the club designated catcher Miguel Montero for assignment.

The injured ankle is the same one Eaton hurt when he tore his anterior cruciate ligament last April. The swelling was so severe, he had to wait for it to go down before undergoing the season-ending knee surgery. It’s also the same one he injured at some point during the Nationals’ home opener Thursday. He exited that game a couple of innings after an awkward slide at home. He wasn’t in the starting lineup again until Sunday night, and then didn’t play on Monday. He was then a late scratch on Tuesday.

“We’re going to be very, very cautious,” Nationals Manager Dave Martinez said. “One, it’s the ankle that he hurt last year. Two, so we don’t have any setbacks on the knee. It’s a bone bruise. But it’s a bad bone bruise and it bothers him. We thought rather let him miss 10 days than let it become three, four weeks.”

Speaking with reporters Tuesday night, Eaton insisted his knee “feels really good.” He said the mobility is the best its been since blowing the knee out a year ago. Martinez echoed those thoughts Wednesday. The manager explained the team’s fear is that Eaton would favor the knee to compensate for the ankle pain and, eventually, hurt the knee again.

“We just want to nip all these things in the bud,” Martinez said. “And hopefully when he comes back the weather gets a little warmer and the turnaround for him will be a lot better.”

Sierra, 29, joined the organization as a nonroster invitee. He stood out in spring training, batting .321 with an .874 OPS and two home runs in 30 spring training games. He was 4 for 12 in four games with Syracuse before he was promoted.

“I loved his at-bats in spring training,” Martinez said. “He works a good at-bat. I talked to [Syracuse Manager Randy Knorr] this morning, and he said he’s working good at-bats in Triple-A too. And [he] plays the outfield really well. He’s got a great arm. Cannon. So I’m looking forward to popping him in there when we need him. He’s going to probably have some big at-bats for us against lefties, but I liked him a lot in spring training.”

Martinez said the club chose Sierra over Andrew Stevenson and Rafael Bautista, two Syracuse outfielders already on the 40-man roster, because they wanted a right-handed bat with big league experience. Stevenson bats left-handed, Bautista right-handed. Both have played in the majors, but Sierra has significantly more service time and 449 career plate appearances on his resume.

As for the other notable Nationals position player on the disabled list, Martinez said Daniel Murphy could be sent to Florida to play in extended spring training games “in the next week or so.” Murphy, who has hit and taken groundballs on the field recently, has checked every box but running the bases. Murphy underwent microfracture knee surgery in October.

BRAVES (6-5)
Ender Inciarte CF
Ozzie Albies 2B
Freddie Freeman 1B
Nick Markakis RF
Kurt Suzuki C
Preston Tucker LF
Dansby Swanson SS
Charlie Culberson 3B
Brandon McCarthy RHP

Brian Goodwin LF
Trea Turner SS
Bryce Harper RF
Anthony Rendon 3B
Matt Adams 1B
Howie Kendrick 2B
Michael A. Taylor CF
Pedro Severino C
A.J. Cole RHP