BOSTON -- The Red Sox's depleted depth chart at third base might soon receive some reinforcements.
Manager John Farrell said Saturday that both Pablo Sandoval (right knee sprain) and Brock Holt (vertigo) are progressing toward a return.
Sandoval, out since April 13, took ground balls Saturday for the second consecutive day, and Farrell said he will travel with the team to St. Louis for a series beginning Monday. After that, the medical staff will determine whether he's ready for a rehab stint.

Farrell said Holt felt good Friday in five innings at third base for Triple-A Pawtucket, where he went 2-for-2. He'll play again Saturday and could return to the Red Sox some time during their upcoming road trip, Farrell said. Holt has played only six games this season due to a variety of maladies, most recently vertigo.
Along with Sandoval and Holt, third baseman Marco Hernandez is currently on the disabled list and could require season-ending surgery. Josh Rutledge and Deven Marrero have manned third base since Hernandez went down last week.

Prior to the team's rash of injuries, Rutledge (27), Marrero (17) and Hernandez (10) had less than 60 career games among them at third base. When compared to everyday men Sandoval (912) and Holt (110), it's easy to see why the Red Sox third basemen have made 13 errors this season, as the fill-ins continue to try to plug the hole at the hot corner as best they can.
"Both sides of the ball are what we're looking for improvement on, whether it's the defensive side or the ability to produce offensively," Farrell said.
Marrero started at third Saturday. Farrell said the 26-year-old could play more moving forward as the team tries to solidify the position defensively.
Hanley still out
Designated hitter Hanley Ramirez remained out of the lineup Saturday as he continues to recover from a right trapezius strain suffered Thursday against the Brewers. Farrell said he hopes Ramirez can return Sunday before the Red Sox head to St. Louis. Chris Young got the start at DH.
Thornburg showing mixed results
Relief pitcher Tyler Thornburg has been out since Spring Training with a right shoulder injury, and Farrell said there's currently no plan for him to return to the mound.
"There's been mixed feedback from Tyler after his throwing sessions," Farrell said. "He's had throwing sessions where it's been up to 60-70 throws from anywhere from 60, 90, 120 to 150 [feet], back in for some more intense, shorter throws.
"But the last two days, after his most recent throwing sessions he's felt a little discomfort/fatigue."
The Red Sox are exploring various treatment options for Thornburg, including further imaging or nerve testing.