Fragile Tulowitzki breaks down again

Troy Tulowitzki has arguably been the best player in baseball this season, leading the National League in slugging percentage and OPS while hitting .347 with 16 home runs. Unfortunately, he's expected to miss four to six weeks after breaking a rib, and his reputation as a brittle player is further cemented.

Last year, a groin injury limited the Colorado Rockies shortstop to just 47 games, and he also missed significant time in 2008 (61 games missed), and 2010 (40 games missed). Manager Walt Weiss had already been cautious about sitting Tulowitzki this year when he was banged up. When healthy, Tulo is on the short list of best players in the game, but it's hard to build a consistent winner around a player who keeps missing large chunks of playing time. The two seasons Tulowitzki remained completed healthy and played 150-plus games the Rockies made the plaoffs.

Rockies fans are familiar with star players who couldn't stay on the field enough. Larry Walker was the team's star from 1996 to 2003, but averaged just 125 games per season over those eight seasons; that's 296 missed games and probably cost Walker a shot at the Hall of Fame. The one season he remained healthy and played 150 games he won the MVP Award.

The Rockies will likely call up infielder Josh Rutledge, who hit his way out of Colorado a couple weeks ago with a .242/.298/.357 line. He played second for Colorado, but came up as a shortstop and should get the first chance to start over Jonathan Herrera. It's obviously a big loss for the Rockies. Baseball-Reference rated Tulowitzki at 3.6 WAR in the 61 games he played, so if he had continued at that level and misses 45 games, that's about 2.5 wins. Rutledge and Herrera are about replacement-level players, maybe a little better, so Tulo's injury will cost the Rockies about two wins.

The one piece of good news is that the Rockies only have one series apiece against the Diamondbacks and Giants through the end of July.

The Rockies are dealing with injuries to Carlos Gonzalez and Dexter Fowler, both listed as day-to-day after leaving Thursday's game. Gonzalez was hit on the foot by a foul ball while in the on-deck circle, and Fowler was hit in the hand by a pitcher. X-rays were negative on both, so they shouldn't miss much, if any, time.