PHOENIX -- Following a relatively unexpected postseason appearance in 2017, the Rockies have to balance continuity with the need to improve and take another step in what they believe is a window to win.
Colorado has a young starting pitching staff, and its Nos. 1 and 2 hitters, center fielder Charlie Blackmon and second baseman DJ LeMahieu, are under club control through next season, with star third baseman Nolan Arenado through 2019.
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But the Rockies have nine free agents and areas to improve if they want to catch the Dodgers and D-backs in the National League West, so they can't afford to spend the winter on autopilot.
Biggest needs
1. Bullpen: Closer Greg Holland was dominant in the first half, less-so in the second, but he still tied the club record with 41 saves. Also, left-hander Jake McGee and right-handed Trade Deadline acquisition Pat Neshek were part of a solid setup crew down the stretch. The problem is Holland will likely test the open market, while McGee and Neshek will be free agents.
Possible free-agent fits: The best move may be to retain Holland, whom most expect to opt for free agency instead of exercising his $15-million club option for 2018, while McGee and Neshek will be hot commodities on the free-agent market. It may be wise to put the dollars into retaining Holland and combing the market for low-cost deals and counting on the continued development of Scott Oberg and Carlos Estevez, as well as a bounceback season from Adam Ottavino, to replace McGee and Neshek. 

If Holland isn't retained, Luke Gregerson, Brandon Morrow and former Rockies closer Huston Street (should the Angels not pick up his option) could be candidates to take on ninth-inning duties. Also, the Rockies are believed to have attempted to pry left-hander Tony Watson from the Pirates before he was traded to the Dodgers at the Deadline, so he could be a free-agent option.
2. Right field: Three-time All-Star Carlos Gonzalez completed a seven-year, $80-million contract with a season that saw him struggle until the final two months. Had left-handed-hitting David Dahl, who hit seven homers with an .859 OPS in 63 games in 2016, not suffered a rib injury in Spring Training and missed the entire season, replacing Gonzalez from within would be the clear option. Raimel Tapia demonstrated speed and hit well when given regular playing time, but he was not adept defensively in right.
Possible FA fits: Did Gonzalez's shaky 2017 lessen his potential market to the point where he would consider a one-year qualifying offer, or even a short club-friendly deal? If not, a power hitter like first baseman Eric Hosmer would make sense with Gerardo Parra getting a chance to hold off the youngsters in right field.

3. Catcher: The plan going into the season was for second-year man Tony Wolters and rookie Tom Murphy to catch a young pitching staff. Unsaid was the Rockies would seek experience along the line. They landed a veteran backstop at the Trade Deadline in Jonathan Lucroy, who saw his bat reignite after coming over from the Rangers.
Possible free-agent fits: The smart move is to retain Lucroy, who is valued by Rockies manager Bud Black. If not, could Colorado make a play for Matt Wieters (should he opt for free agency rather than an $11-million player option)?

Gray areas
General offense: Even with outstanding seasons at the top of the lineup, the Rockies' offense was inconsistent at times. Improved seasons from Trevor Story and Ian Desmond, who was on the disabled list three times in his first of a five-year deal, and more consistency from Parra would help. But Rockies general manager Jeff Bridich has said many times he is willing to listen to "anything and everything," so you can't put a trade to shake up the lineup past him. There is starting pitching depth in their Minor League system, although the Rockies have steadfastly refused to trade it.
Bench:Mark Reynolds, who hit 30 homers and took over at first base when Desmond was out early in the season, and Alexi Amarista, who was mostly a defensive insurance policy, are free agents and provided production and versatility that will need to be replaced if not retained.

X-factor
Starting pitching: Right-hander Jon Gray and southpaw Tyler Anderson just completed their second Major League seasons with promise, and righty Chad Bettis should benefit from a normal offseason after battling testicular cancer from November until his return in August. Four rookies -- righties German Marquez, Antonio Senzatela and Jeff Hoffman and lefty Kyle Freeland -- all had high moments, but all except for Marquez wore out during the second half. Do the Rockies interject a veteran to the group?