If the Diamondbacks get even a little production from the Big Unit, they should repeat as NL West champs. Doug Pensinger/Getty Images Sport

By Joe Sheehan, BaseballProspectus.com

The home to the senior circuit's surprise pennant-winning Rockies and the equally surprising division-champion Diamondbacks, those feats guarantee those teams nothing, because this is a division that has four contenders for the division title.

Arizona Diamondbacks

Where: Tucson, Arizona (Cactus League)

2007 record: 90-72 (1st, NL West)

New guys: Billy Buckner, Chris Burke, Emiliano Fruto, Juan Gutierrez, Dan Haren, Chad Qualls

Gone guys: Alberto Callaspo, Tony Clark, Livan Hernandez, Carlos Quentin, Jose Valverde, Bob Wickman

Wow, he's still here? Chad Tracy has been rendered into trade bait by Mark Reynolds, although there's some speculation that Tracy could play first base, with Conor Jackson being the one dangled instead. In any case, one of these three will not be happy with his playing time. Tracy is the oldest and most likely to go.

Winter grade: A-. Josh Byrnes added the missing piece by trading for a top-tier starting pitcher in Haren, dealing many pieces from a deep system while not giving up the very best of it. Shuffling Valverde out at his likely peak was aggressive, the kind of year-too-early move that Branch Rickey would admire.

NRI (Non-Roster Invite) to watch: Tim Raines Jr. is no longer a prospect, but as a minor league veteran, he's become a good candidate to be a useful fourth outfielder, with an excellent stolen-base percentage (55-for-64 in 2006 and '07) and enough OBP and defense to be more than worth a roster spot. He'd be an excellent fit backing up the Diamondbacks' righty-heavy outfield.

Job battle to track: Bob Melvin anointed Brandon Lyon as his closer heading into camp, as much to spike a potential controversy as anything else. In the long term, it's Juan Cruz who has the power stuff to fit best in the role. Tony Pena and Chad Qualls may also make bids if and when Lyon falters.

One move to make: This is a deep and stable roster that could feature one of the best benches in the game. Trading Tracy should be a priority if and only if using him, Reynolds, and Jackson in a rotation will cause non-performance problems in the clubhouse. Having the lefty bat as an option in a Mike Lamb role would be a significant bonus. If Raines isn't the answer, acquiring a left-handed fourth outfielder -- Johnny Damon would actually be a pretty good fit -- in-season would help.

The Diamondbacks won the West last season on the strength of a deep bullpen and good fortune. The talent level of the team is much better now, however, as young players like Stephen Drew, Chris B. Young, and Conor Jackson develop, and are joined by Haren, who represents about a four-win improvement over the starters he's replaced. The D'backs won't have a walk, but they should be the favorite in a close race. If Randy Johnson can make even 20 starts, they'll be playing in October.

Colorado Rockies

Where: Tucson, Arizona (Cactus League)

2007 record: 90-73 (2nd, NL West)

New guys: Jose Capellan, Josh Towers, Luis Vizcaino, Kip Wells

Gone guys: Jeremy Affeldt, Jamey Carroll, Josh Fogg, LaTroy Hawkins, Jorge Julio, Rodrigo Lopez, Kazuo Matsui

Wow, he's still here? Yorvit Torrealba, playoff hero, had all but signed a deal to catch for the Mets when the Mets changed their minds. The Rockies subsequently re-signed him to a two-year deal.

Winter grade: C. It could be lower, but in fairness, there wasn't much for them to do. Other than fill the second-base hole vacated by Matsui -- for which the external candidates were unimpressive -- Dan O'Dowd didn't have much in the way of transaction options. It does raise eyebrows, however, when a team is this passive in the wake of a successful season. Then again, the Red Sox did even less this winter.

NRI to watch: Casey Weathers, the Rockies' first pick in the '07 draft, was the closer at Vanderbilt a year ago and could have that job in Denver by the end of the season. With a high-90s fastball and great slider, he has the dominant stuff that no one in the current Rockies' bullpen possesses. At the least, he'll be a key mid-season addition.

Job battle to track: Everybody but Eric Young Sr. is taking a run at the second-base job. The team did sign Marcus Giles to a minor league deal, although he sits behind glove man Jayson Nix on the depth chart. Omar Quintanilla, Clint Barmes, and perhaps even Ian Stewart could get some time at second this spring.

One move to make: When Mark Redman and Kip Wells are the fallback positions, it's hard to suggest that a team send its best live arm to the minors. In the big picture, though, both the Rockies and Franklin Morales would benefit by the lefty spending a few months at Triple-A. He's still raw, and needs work on both his mechanics and his secondary pitches.

The Rockies appeared to rest on their laurels after a historic World Series run last fall. Actually, they just enjoyed the fruits of a roster consisting primarily of players under their control. With the exception of second base, the key contributors to last year's success all return, and while you can expect some fallback from Matt Holliday and perhaps Brad Hawpe, there's also the potential for improvement behind the plate -- where Chris Iannetta should play more -- and in center field, where a healthy Willy Taveras would be an asset. The key again will be how the defense, one of the two best in baseball last year, holds up behind a staff that puts it in play. At the least, the Rockies will again be in the wild-card mix.

Los Angeles Dodgers

Where: Vero Beach, Florida (Grapefruit League)

2007 record: 82-80 (4th, NL West)

New guys: Gary Bennett, Andruw Jones, Hiroki Kuroda

Gone guys: Luis Gonzalez, Mike Lieberthal, Mark Hendrickson, Ramon Martinez (NRI), Olmedo Saenz, David Wells, Randy Wolf

Wow, he's still here? Esteban Loaiza was lousy (8.34 ERA in five starts) after being acquired at the waiver-trade deadline in August. However, his contract runs another year, so he'll be at the back end of the rotation.

Winter grade: B. The Jones signing was an excellent case of buying low, and Kuroda's contract is a good gamble given the price of MLB free agent starting pitchers. Better still, the Dodgers avoided making another bad trade, retaining all of their young talent.

NRI to watch: Not that the Dodgers need another outfielder, but John-Ford Griffin is in camp. The one-time first-round pick is now a 28-year-old with no upside. However, and take this with a grain of salt, he has a career line of .304/.370/.696 in 27 plate appearances. Aren't you just a little curious?

Job battle to track: There are four outfielders for three spots, and it's excruciatingly clear to anyone familiar with baseball who ranks fourth among them. However, the likelihood that the Dodgers relegate Juan Pierre to a bench role is nil. Every PA he takes from Matt Kemp and Andre Ethier is a mistake.

One move to make: Trading Pierre for whatever he'll bring back, even if it means eating $10-15 million. Pierre would actually be a decent extra outfielder; it's just not likely that the Dodgers would do that, or that he would be all that happy in the role. Having Pierre around just increases the chance that he'll take time away from better players. There are people who don't like it when we say players aren't good, and saying this about a known nice guy like Pierre tends to fire up the opponents of performance analysis. Playing him regularly on a corner is just baseball malpractice, however, and the Dodgers have to avoid that temptation.

Ned Colletti has squandered a fair amount of scouting director Logan White's work in his time as the Dodgers' GM, but he avoided doing so this winter. Thanks to that, he heads into the spring with his best team, and with the best chance of having that team play. There remains the need to push Pierre and Nomar Garciaparra into supporting roles, the latter so that OBP machine Andy LaRoche can take over at third base. The "right" Dodger lineup can win 94 games and the division. How Joe Torre apportions playing time in a situation not dissimilar to the 1996 Yankees will determine whether the Dodgers fulfill their potential.

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