Tulowitzki is usually the best, but he wasn't this season.
Dan O'Dowd built the Rockies on the run this season when an offseason full of moves didn't seem to pan out. He traded Miguel Olivo for Jose Lopez because Chris Iannetta was ready to come back. Lopez was supposed to solidify second base offensively and defensively. That never happened. Iannetta kept his end of the bargain, but Lopez never hit his weight, so off he went.
Mark Ellis was acquired from Oakland to take his place and he did so ably. Meanwhile, late in the year, he also picked up Kevin Kouzmanoff from Oakland. Third base had been a revolving door in Denver since the days of Vinny Castilla. As it turns out, Kouzmanoff didn't work out either, but we can't blame O'Dowd. He at least tried right?
DER: .688 (20th)
RA: 714 (27th)
FLD%: .984 (13th)
Baseball Reference: -43 runs (28th)
Fangraphs: -16.9 runs (24th)
Fielding Bible: +16 runs (12th)
Baseball Prospectus: -6.3 runs (23rd)
Composite Runs: -12.6 runs
Ultimately, we grade on results, but when we look at what Dan O'Dowd did we have to conclude that he gets it. He tried to put solid fielders at every spot and just couldn't seem to. Ty Wigginton got more time at third base than anyone, but O'Dowd's moves indicated that wasn't his intention. The lack of performance from the outfielders also was puzzling. Different sources had Carlos Gonzalez as positive overall, but they never seemed to figure out where to play him.
Seth Smith and Dexter Fowler were also below average, but when you watch them you think they should be better. It is highly possible that everything just seemed to work against the Rockies this year with the gloves. These things happen. Sometimes the best laid plans of mice and men just don't stretch as far as you think they will.
Troy Tulowitzki is the poster child for fielding sabermetrics. A few years ago we used them to prove he was the best defensive shortstop in baseball. This season we use them to prove that players have ups and downs with the glove just as often as they do with the bat. Tulowitzki was legitimately good this year, but he wasn't the best National League shortstop defensively by any stretch.
Tulow will end up winning the Gold Glove this year, but he doesn't deserve it. By all accounts he should have two or three on his mantle already. This is the Rockies story this year. Those that have been great were not great. Those expected to be good were not good. O'Dowd deserves credit for using analysis to build a good defensive team. Sometimes all the analysis in the world can't predict a collective slump.
All of the regulars either projected to be good or were good. Then, there was Ty Wigginton. Wigginton is one of those guys that gets everything possible out of his body. God gave him the ability to field multiple positions, but didn't give him the ability to field any of them well. In his career he's played every infield position except for shortstop and even has dabbled in some left field. He can't play any of them well, but he's a great guy to have around anyway.
On the surface, it would seem like third base is the only position in a state of flux. Mark Ellis is technically a free agent, but the Rockies want him back. Ellis wants to be back and both sides need each other. For third base, they can either hold their nose and go with a full season of Wigginton or they can bring in a bigger name. David Wright's name keeps getting floated around, but that would do nothing for them defensively.
Iannetta seems entrenched at third base, but Wilin Rosario and some other young catchers appear ready to take his job. Iannetta is solid offensively and defensively, so if they are ready to make such a move he might fetch quite a bit on the open market. That's going to be tricky given contract situations on either side, but he could be the basis of a trade with the Mets.
In most seasons, Troy Tulowitzki is the best fielding shortstop in baseball. Mark Ellis has the capability of being that if he plays a whole season in the same place. Todd Helton isn't brilliant, but he is above average. If the Rockies find a consistent home for Carlos Gonzalez he could be one of the better defensive outfielders as well. That's four solid to good defenders without breaking a sweat.
Then, throw in Dexter Fowler's natural ability and Chris Iannetta's defense (if he stays) and you have the makings for one of the better defensive teams in the National League. My inclination would be to keep everything together and expect that everyone's natural ability would take care of itself.