By Peter Abraham, Globe Staff

FORT MYERS, Fla. — Has the time come to worry about whether David Ortiz will be available for Opening Day?

Not yet, manager John Farrell said Sunday. The Red Sox still believe their designated hitter will be ready. But the Sox have played 10 games in spring training and Ortiz has yet to get on the field.

He was scheduled to go through a base-running drill Sunday but did not because of discomfort in his right Achilles' tendon. The tentative plan is try again on Monday.

“They made a decision at the time he was going to run that he felt just a little bit of soreness and they backed off it,” Farrell said.

The Red Sox, Farrell said, ideally would want Ortiz to run the bases two days in a row before he gets into a game.

Ortiz said he felt good running the bases Saturday and felt sore later in the day. The issue, he said, is not his Achilles' but some calcification that has occurred.

“The doctors are being smart about the things that we are doing,” Ortiz said. “I told them that when I get in, I want to be in. I don’t want to go in for a week and come back out and not be playing and this and that. I want to be good to go.”

Ortiz said that doctors have told him to expect soreness as he increases his work on the field. He said that Red Sox staffers, particularly therapist Dan Dyrek, have his confidence.

“We’re doing the right things,” he said. “I’m going to get there.

Starting Monday, the Red Sox have 25 days of games remaining. To be ready for the season, Ortiz likely would need at least 25-35 plate appearances. Given that he would not play every day, Ortiz would need to start playing sometime soon.