Eaton to disabled list, Sierra called up from Triple-A

The Nationals announced before Wednesday's series finale against the Braves that they have placed outfielder Adam Eaton on the 10-day disabled list and purchased the contract of outfielder Moisés Sierra from Triple-A Syracuse. Eaton has a bone bruise in his left ankle.

Manager Davey Martinez said the Nats will operate very carefully with Eaton due to his injury history.

"I think for the most part we are going to be very, very cautious," Martinez said. "One is, it's the ankle he hurt last year. Two, that we don't want any setbacks on his knee. It's bone bruise, but it's a bad bone bruise. It bothers him. We thought rather let him miss 10 days than it becomes three, four weeks. It's going to be something that's going to be monitored day-to-day and see where he's at (and) when he's ready."

Will the Nats rethink the playing time regimen for Eaton when he returns? Could they adjust to a playing schedule similar to Ryan Zimmerman where Eaton plays on three or four times a week?

"He says his knee is fine. Our biggest concern was his knee," Martinez said. "It says his knee is absolutely fine. He feels better every day. We just want to nip all these other things in the bud. Hopefully, when he comes back, the weather gets a little warmer, the turnaround will be a lot better. Rather than have this linger and linger and it becomes a bigger issue, we'd rather just take care of it now."

Sierra took the place on the 40-man roster of catcher Miguel Montero, who was designated for assignment. Sierra impressed in Syracuse, getting a hit in each of his first four games. He also hit well in spring training for Martinez: .321 (17-for-53) with three doubles, two home runs, 11 RBIs and eight runs scored in 30 games.

"I loved his at-bats in spring training. He works a good at-bat," Martinez said. "I talked to (Syracuse manager) Randy (Knorr) this morning, said he's working good at-bats in Triple-A, too. Plays the outfield fairly well, has got a great arm, a cannon. I'm looking forward to popping him in there when we need him. He's probably going to have some big at-bats for us against lefties. I liked him a lot in spring training."

Andrew Stevenson and Rafael Bautista each had experience with the Nats last season. Why didn't Martinez pick them this time?

"We felt like at this particular time, we wanted a right-handed bat and he gives us that bat off the bench," Martinez said. "Veteran guy, been in the big leagues before. His at-bats in spring training have really impressed me."

Stevenson is just 2-for-19 to start the season with the Chiefs, while Bautista is 3-for-24 out of the blocks with Double-A Harrisburg.

Sierra is thrilled to get another shot at the big leagues. He played for the Blue Jays and White Sox from 2012-2014.

"I'd like to give thanks to the organization, to God, to my family for this opportunity," Sierra said through interpreter Octavio Martinez. "I did have a good spring training and a good start to the season. Hopefully, this continues. I'm here to help out the team any way I can ... and keep working hard, keep producing the way I have so far."

Sierra talked about his focus at the plate and how that has helped him put together good at-bats and build from there.

"I think the only big thing with me was getting a good routine down," Sierra said. "Keep working both offensively and defensively like I have and that helped me carry on into spring training, have a real good spring training for me. I just hope to keep adding to that."

Sierra said he is different player than he was back when he played 180 games in Toronto and Chicago. Most of his games have come in right field - 138 of them - but he also has experience in left and center field.

"The biggest thing I think is I've gained a lot of experience," Sierra said. "I feel like I can bring more to the team right now. The experience has helped me grow as a player. I feel like that's going to help me perform a lot better up here now and help out anyway I can."

Sierra was the designated hitter in Monday's game when Syracuse center fielder Victor Robles, the Nats' top prospect, went down with a hyperextended left elbow.

"We felt very bad," Sierra said. "It was a very unfortunate situation. ... We spoke after the game, tried to lift him up a little bit and give him support. We hope he gets better very, very soon."