While the consensus had the team attempting to trade Parra following Kubel’s signing, the Diamondbacks stood pat and attempted to use everyone effectively. Top prospect Adam Eaton then knocked down the door to the majors at the end of the season, put up solid numbers across 103 major league plate appearances, and appeared to be the odds-on favorite for the starting centerfield gig.
Chris Young was dealt to the Athletics to make room for Eaton but the Diamondbacks were right back at square one. They had four starting outfielders for three spots and clear needs elsewhere that could get fixed through a trade. Regardless, it seemed like they stopped looking at free agent outfielders and were focused on subtracting from the group, whether it was a mega-deal involving Upton or a smaller deal for one of Kubel or Parra.
Kevin Towers and Co., defied these expectations over the weekend by signing Cody Ross to a three-year, $26 million contract. The move instantly put Kubel and Parra back on the trading block as there is simply no way the Diamondbacks enter the season with even more of a starting outfield surplus than last year. However, signing Ross was a questionable decision because he and Kubel have been similarly valuable players over the last couple of seasons. They essentially already had another form of Ross on the roster and it’s unclear if the team will be able to extract full value in a subsequent Kubel trade now that it very clearly has to move one of its outfielders.
Ross and Kubel aren’t identical players but their numbers over the last two seasons are very similar. Ross offers better fielding and baserunning while Kubel has him beat in the on-base and slugging departments. Kubel is also one year Ross’s junior. Here are some of their pertinent numbers over the last two seasons:
Ross: 989 PA, 9.2% BB, 22.8% K, .254/.326/.446, .334 wOBA, 109 wRC+
Kubel: 972 PA, 9.2% BB, 24.4% K, .261/.329/.476, .345 wOBA, 113 wRC+
When normalized for league and park there is really no discernible difference between the two at the plate and the defensive gap among them — Ross at -3, Kubel at -7 — isn’t that substantial. Why then would the Diamondbacks make this move if Ross isn’t a clear upgrade and still required a fairly lucrative three-year commitment?
The likeliest answer is the Diamondbacks wanted to continue using Parra as the roving fourth outfielder but also wanted to use their outfield depth to help solve another problem area. Parra would platoon on occasion and help spell the other starting outfielders while reaching a certain, likely pre-established, plate appearances threshold.
Kubel is guaranteed one more year on his deal and an acquiring team may find unloading a prospect for a one-year commitment more palatable than signing Ross. In this scenario, the Diamondbacks replace Kubel with a slightly better — if not more expensive — version of himself, while using the actual Kubel to acquire a needed prospect or player.
Perhaps the Diamondbacks intended on spending Ross’s money to fix these areas of need directly, but found no one to their liking or had their efforts rebuked. Perhaps, through discussions with various other teams over the course of the offseason, they feel confident that Kubel is a valuable trade target for teams that would miss out on Ross.
Perhaps they wanted to keep some form of Kubel around on a three-year extension while using another form of him to bolster the infield or pitching staff. This was a seemingly unnecessary move on the surface but one that could pay dividends if Ross plays well and Kubel brings back solid value in a trade.
Teams don’t generally continue to seek players in areas where a logjam or surplus already exists, because of the uncertainty in what they could get by moving the player made expendable by such a move. The Diamondbacks potentially have a very good outfield and were willing to take that risk to make a slight upgrade over a player they already had, while using the latter player to help them through a trade.
The first part of this process is now complete, but what they get for Kubel is a partial factor in determining the initial value of this signing.