Last week, Jon Paul Morosi of Fox Sports reported that the Cardinals had engaged in trade dialogue with the Colorado Rockies about acquiring an outfielder. He listed Carlos Gonzalez, Charlie Blackmon, and Corey Dickerson as the outfielders that would potentially be available.
Because they failed to sign Jason Heyward, the Cardinals could still look to add another outfielder, although John Mozeliak has expressed confidence in the team's current group of outfielders and does not seem inclined to pursue any of the remaining free agent outfield options. Mozeliak may find a better fit on the trade market, and the Colorado Rockies have three outfielders they could potentially look to trade.
When healthy, Gonzalez has been one of the better outfielders in baseball over the last several years. His best season was in 2010 (5.8 fWAR, 144 wRC+), but he was still an extremely productive outfielder as recently as 2013, when he posted a 146 wRC+ in 426 plate appearances. He draws a lot of walks (7.8 percent career walk rate) and hits for a lot of power (career .233 ISO), but his numbers are likely inflated as a result of playing half his games at Coors Field.
In his career, Gonzalez has hit .324/.382/.604 (137 wRC+) at home and .255/.310/.455 (101 wRC+) on the road. We cannot attribute all of this difference to Coors Field, since players tend to do better at home anyway. In 2015, all major league hitters posted a 105 wRC+ at home and a 95 wRC+ on the road. Still Gonzalez's home/road difference is much larger than this, even though wRC+ is a park-adjusted statistic. We would expect to see all hitters' raw statistics improve as a result of playing more games at Coors Field, but Gonzalez's approach seems to play particularly well in Colorado. This could be due to the fact that Gonzalez's fly ball rate is a couple percentage points higher than league average.
Gonzalez's home/road splits make me hesitant to believe that he would be a significant improvement over the Cardinals' current options. He is also owed $37 million over the next two years and has a long injury history. The Cardinals should pass on Gonzalez, unless they can acquire him without giving up players of significant value.
I honestly have no idea why the Cardinals would be seriously interested in Blackmon. He would almost certainly be the team's fifth best outfielder, as he has been no better than a league average hitter in his career (97 wRC+) while posting below average defensive metrics in center field (-13 DRS, -16.7 UZR). Like Gonzalez, he appears to be a product of Coors Field, as he has posted a 79 wRC+ on the road in his career. He is cheap and under team control for another three years, but at age 29, he has little upside, and he would not represent a significant improvement for the Cardinals.
Dickerson is an intriguing option, as he is only 26 and has posted excellent offensive numbers in his young career (124 wRC+ in 925 plate appearances). His numbers appear to be boosted by a career .347 BABIP, but this is backed up by an career hard contact rate of 36 percent. (League average in 2015 was 28.8 percent.) Unfortunately, he has bigger home/road splits than Gonzalez and Blackmon. At Coors Field, he has a ridiculous batting line of .355/.410/.675 (165 wRC+) while he has posted a subpar .249/286/.410 batting line on the road, good for a wRC+ of 89.
Dickerson's defensive metrics are also concerning as he has posted -9 DRS and -12 UZR in 1455 1/3 innings in left field, which is one of the lowest positions on the defensive spectrum. Even if he can be a well above average hitter away from Coors Field, his outfield defense will take away a good portion of his value. Dickerson is cheap and under team control for another four years, so he would potentially be able to take over in left field once Matt Holliday leaves. With that being said, the Cardinals would need to be convinced that he can produce outside of Coors Field before they attempt to acquire him, and so far the results are not encouraging.
In all honesty, I am not thrilled by the prospect of the Cardinals acquiring any of the Rockies' three outfielders. They have not shown the ability to hit well outside of Coors Field, and I am not convinced that they would represent an upgrade over the team's in-house options. The Cardinals can afford to go into the 2016 season with the outfielders currently on their roster, but they should be opportunistic in looking for improvements. Unfortunately, acquiring a Rockies outfielder does not appear to be a very appealing opportunity for the Cardinals.