There are injuries, and then there are big injuries. And four big ones that could have a big effect on the regular season happened this week.

• Troy Tulowitzki, Rockies: The second-year shortstop, a pillar for the NL champs last season, tore a tendon in his left quadriceps near his hip. Tulowitzki was off to an ice-cold start, hitting .152, and now will most likely will be out until the All-Star break.
• Jorge Posada, Yankees: After more than a decade behind the plate, Posada is on the disabled list for the first time in his career with a sore shoulder. Doctors don't believe he needs surgery, but it's all wait-and-see (and hope) in New York. The Yankees' backup catcher, Jose Molina, is a capable backstop but can't come close to replacing Posada's production in the lineup. Posada hopes to return in six weeks, if his shoulder responds to rest.
• Yovani Gallardo, Brewers: Gallardo isn't a household name, but was one of the most promising pitchers in baseball, and everybody in Milwaukee knows who the 22-year-old righty is. He tore a knee ligament avoiding a collision at first base and is out for the season. This could tip the scales in the NL Central more toward the Cubs and Cardinals.
• Phil Hughes, Yankees: The promising second-year pitcher has a stress fracture of a rib in his side and is out until at least July. It was a bizarre tale as it looked like a phantom injury, an oblique strain designed to give Hughes a couple of minor-league starts to work through some problems (he is 0-4 with a 9.00 ERA). But now a team already not deep with starting pitchers is searching for some kind of solution. I wouldn't be surprised if the Yankees soon trade for an innings-eating type of starter - not a star - if the price is right.