NEW YORK -- There have been few positive developments on the Mets' injury front for weeks. However, the tide seems to be turning.
Manager Mickey Callaway said on Sunday that third baseman Todd Frazier is expected to come off the 10-day disabled list and rejoin the team for the two-game series against the Orioles that begins on Tuesday. He also said that injured outfielder Yoenis Cespedes -- out for nearly three weeks now -- would take batting practice on Tuesday and might not need to go on a Minor League rehab assignment before he returns to the starting lineup.

Frazier had a .769 OPS with five homers and 21 RBIs in 32 games before a left hamstring strain forced him to the DL on May 8. Entering play Sunday, the Mets had scored three runs or fewer in a dozen games since Frazier went to the DL.
Cespedes had a .790 OPS with eight home runs and 28 RBIs in 37 games before a strained right hip flexor shelved him on May 16.
"He's in a really good spot, getting on his feet on and off," Callaway said of Cespedes. "We're going to try to get him some live at-bats on Tuesday against a live pitcher and then after that we're just going to lean on him and see what he needs. If he needs a few games in the Minor Leagues or not, things like that. But he's going to get some live at-bats on Tuesday."
When asked whether Callaway would be comfortable with Cespedes not taking a Minor League rehab assignment he replied, "He's going to get live at-bats. It doesn't matter if it's in a [simulated] game or a real game. It's a challenge, we need him back."
Frazier played all nine innings on Saturday for Triple-A Las Vegas -- his third Minor League rehab game -- and was 2-for-3 with two RBIs, two walks and a run scored.
Cespedes, Frazier and Wilmer Flores -- three right-handed hitters -- are all sidelined and Callaway went with a lineup with five left-handed hitters against Cubs southpaw Jonathan Lester on Sunday. 
"Right now, we need to get some of our key pieces back," Callaway said. "If you look at our lineup, we're missing our two-main right-handed bats.
"We're just trying to hold the fort down until those guys get back and then we'll be in a good place," he added. "We'll have all those guys back that we had at the beginning of the season and we can start trying to get on a roll again."
• Right-hander Anthony Swarzak, out since April 1 with a left oblique injury, pitched two scoreless innings for Las Vegas on Saturday. He was scheduled to pitch again for the 51s on Sunday and Callaway said it would be Swarzak's final rehab game before returning to the Mets.
• Catcher Devin Mesoraco is considered day to day after feeling tightness in his hamstring on Saturday.