Both Michael Morse and Adam LaRoche will remain sidelined from baseball activities until Sunday as the Nationals monitor Morse’s strained right lat and LaRoche’s bruised left foot, Manager Davey Johnson said.

While the Nationals have stressed they are unworried about both injuries, Johnson raised the possibility today, for the first time, that the Nationals could be without their opening day first baseman or left fielder for opening day.

“We’re going to be ultra-cautious,” Johnson said. “I’m going to monitor them real close. I’m not going to push them to get them ready by opening day if I think there’d be a setback to any of them.”

If either player missed opening day, it would likely only be a short-term absence and not a stay on the disabled list. Both Morse and LaRoche have said their only concern is getting enough at-bats to feel confident in their timing at the plate.

“Morse is feeling like he’s getting close,” Johnson said. “Doctors and trainers want to sit on him, so we’ll sit on him more.”

Morse has been running, but the Nationals have prevented him from hitting or throwing. They have also restricted him from lifting weights, but today Johnson saw Morse standing around in the weight room. “I think he’s going a little stir crazy,” Johnson said.

“I’m pulling my hair out,” Morse said.

More on the Nationals:

Updates from Nats vs. Braves

Strasburg to start opening day

Boswell: Harper in center field makes sense

Top-of-the-order hitters need to improve

Rodriguez still dominant

Smooth sailing for Strasburg

Rizzo explains his Harper decision

Nats-Mets updates

Lee County wants to negotiate with Nats

Updates on Storen, Morse, Wang

Ankiel returns to lineup

Spring training heats up