PHOENIX -- The shakeup in the D-backs' front office and coaching staff continued Tuesday, as general manager Mike Hazen and manager Torey Lovullo work to get their own people in place.
On Monday, the D-backs let third-base coach Matt Williams and assistant hitting coach Mark Grace know that they would not be retained. On Tuesday, they delivered similar news to bullpen coach Garvin Alston.
"Very difficult decisions with the staff," Hazen said during the second day of the General Managers Meetings. "It's not something we take lightly. We had to give the manager some freedom to put some of his staff together. I think that it's a responsibility that we have."
While Hazen would not confirm any other staff changes, sources said that bench coach Glenn Sherlock was told his role for next year was uncertain, but that he would not be the bench coach. It's possible Sherlock could still wind up on the Major League staff or else be offered another job in the organization.
Sources also said that pitching coach Mike Butcher and first-base coach Dave McKay would be back next year.
That leaves only the status of hitting coach Dave Magadan unknown.
"I'm just not going to confirm anything right now with any of that stuff, out of fairness to our ability to put the entire staff together," Hazen said.
In the front office, the team lost assistant GM Bryan Minetti, who was named special assistant to GM Matt Klentak in Philadelphia.
Meanwhile, the D-backs hired Jared Porter as senior vice president and assistant GM, and they promoted farm director Mike Bell to vice president of player development and Josh Barfield to assistant director of professional scouting.
Porter had been the Cubs' director of professional scouting for the past 13 months after he previously spent 12 seasons in the Red Sox's front office, during which time they won three World Series.
"It's coming into shape," Hazen said of his front office. "We still have some additions to make, but I think hopefully right now most of the losses, we know what those are at this point in that time."
Now that staff will try to figure out how to improve a team that finished 69-93 this past season.

The two biggest priorities are improving the bullpen, which ranked 27th in ERA in all of baseball, as well as the outfield defense.
"We're going to look for any and all available impact bullpen guys," Hazen said. "Guys that can pitch in high-leverage situations, we need to make sure we're seizing opportunities where we can. We need to gather as much information as we can. Trying to rebuild any phase of the team is complicated in one offseason, but it's something we're going to be focused on."
Some of the D-backs' outfield defense issues will be solved by a return to health of center fielder A.J. Pollock and right fielder David Peralta, but Yasmany Tomás has not proven to be adept in the field, and the team may need to move him.