PHOENIX -- The D-backs looked like the big winners of last offseason when they surprised baseball by signing Zack Greinke to a six-year, $206.5 million deal and acquiring Shelby Miller -- even though some balked at the cost -- to improve their rotation.
The 2016 season, however, was a disappointment, and as the D-backs head into this offseason, many questions must be answered.
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At the top of the list is who will be the one making the decisions, with neither chief baseball officer Tony La Russa nor general manager Dave Stewart assured of being offered new contracts.
Once the front office is settled, the organization will have to figure out whether the results of 2016 represent an aberration caused by injuries or whether full-scale changes to the roster will be needed.
As they tried to do last year, the D-backs will again take strides to improve their pitching staff. Changes must be made to the bullpen, and the club will have to decide whether to break up the young nucleus in the rotation or bank on the possibility of enough of their starters taking a step forward.
While the D-backs spent a significant amount of money last offseason, they probably will not have much to work with this time around, unless they are able to move some contracts.
When Spring Training opened, the D-backs had hopes of playing deep into October. Instead, it will be a month spent trying to figure out what the right moves will be this winter.
Arbitration-eligible: SP Rubby De La Rosa, RP Randall Delgado, C Welington Castillo, C Chris Herrmann, INF Jean Segura, SP Patrick Corbin, SP Miller, INF Chris Owings and C Tuffy Gosewisch
Free agents: OF Rickie Weeks Jr. and RP Daniel Hudson
Rotation: Heading into next season, unless major trades are made, the rotation figures to consist of the same group that saw action in 2016. The D-backs will hope that Greinke can recapture the form he enjoyed prior to 2016 and that he is able to stay healthy. Maybe having a year with Arizona under his belt will help Miller feel more comfortable and relaxed. Corbin showed enough after being demoted to the bullpen that he will be back in the rotation, and Robbie Ray also figures to have a spot. Archie Bradley made progress and should compete for a spot, as will Zack Godley, Matt Koch and Braden Shipley.

Bullpen: This will, no doubt, be a point of emphasis during the offseason, because it is an area that must improve. The D-backs could look to bring back Hudson at the right price. Young right-handers Jake Barrett and Enrique Burgos both have upside, but neither showed enough in the final months of 2016 to show he could be counted on to close games.
Catcher: Castillo figures to once again be the starting catcher after putting together another solid year at the plate. Herrmann, who was acquired last offseason, intrigued the D-backs with his bat, even though he missed significant time due to injury. Herrmann's versatility -- he even started a game in center in 2016 -- makes it easier for the D-backs to carry three catchers. Gosewisch is popular with the pitching staff for his game-calling acumen and his blocking ability.

First base: This is a position the D-backs have not had to worry about since 2011, and they will not need to for another three seasons, thanks to Paul Goldschmidt. Coming up with a backup for him is never an issue, since he rarely takes a day off.
Second base: Segura was a huge part of the offense in 2016 and is under club control for another two seasons. The D-backs do have some infield decisions to make, however, that could affect Segura. If they go with Nick Ahmed again at shortstop, they would leave Owings without a position. Would the club consider dealing Segura? His trade value may never be higher, and he could potentially bring back some bullpen help.

Shortstop: The D-backs love Ahmed's defense, but he'll need to produce a little more at the plate. It's hard to know if some of his offensive troubles this year were the result of his trying to play through a hip injury. Again, the team has options here with Segura and Owings also able to play the position.
Third base:Jake Lamb did nothing to lose his starting job after having a breakout season at the plate. The bigger question is what the D-backs will do with Brandon Drury. Third base is Drury's best position, but it's spoken for, and it's also crowded at second base, another position he can play. Drury showed he can be a valuable weapon at the plate when given consistent playing time, but even though he showed improved defense in the outfield as the season wore on, it's not an ideal fit for him. Phil Gosselin gets overlooked, but he's a valuable utility player who came up with some big pinch-hit knocks for the D-backs this year.

Outfield: The outfield defense was very poor in 2016, but that should improve simply with the return to health of center fielder A.J. Pollock and right fielder David Peralta, both of whom missed most of the season. Yasmany Tomás put up decent power numbers, but he is very limited defensively. Tomas' annual salary will start to rise precipitously in a couple of years, so it may behoove the D-backs to see what his trade value is now, as he could be a valuable piece for an American League team. Owings showed that he could play the outfield, and Mitch Haniger would make a valuable backup at all three positions. Drury is also a possibility at one of the corner-outfield spots.