We all hate them, but injuries are part of the game. We're only in the fourth week of this NFL season, and there have been so many injuries, especially to the quarterback. Some of the best players are currently out, such as Dez Bryant and Tony Romo, for an extended period time.

Here are some of the most notable injuries for Week 4.

Andrew Luck

It hasn't been a great start for the Indianapolis Colts starting quarterback. Andrew Luck has a shoulder injury, and his status for Week 4 remains "uncertain" against the Jacksonville Jaguars. Luck was limited in practices this week. The Colts signed quarterback Josh Johnson on Friday. Luck has never missed a game in his career.

DeMarco Murray

The Philadelphia Eagles may be without DeMarco Murray, for better or for worse. Murray was limited in practice for most of the week, but on Thursday he did participate in practice and limited contact drills. Murray did not play last week against the New York Jets.

Victor Cruz

Victor Cruz will not be playing for the New York Giants this weekend against the Buffalo Bills. A calf injury will keep him out this week. The Giants have been working out other free agent wide receivers the past few days such as Wes Welker and Hakeem Nicks.

Drew Brees

Drew Brees was unable to play last week in a loss to the Carolina Panthers. Luke McCown may get the start again. Brees has been limited in practice this week, but he recently said "nothing is going to keep me off the field this Sunday." We'll find out soon enough.

LeSean McCoy

The Bills will be without their best running back in LeSean McCoy against the Giants. McCoy has a hamstring injury, and to make matters worse for Rex Ryan, Sammy Watkins is out with a calf injury. This will a very tough task for the Bills.

Luke Kuechly

Things aren't looking very positive for Kuechly right now. According to NFL reports, most likely Kuechly will miss his third consecutive game for the Carolina Panthers. The Panthers will take on the Tampa Bay Buccaneers this weekend.

Jay Cutler

Jay Cutler's hamstring injury may keep him out again. He is presently listed as "day to day" with the injury, but hopes aren't very high in the Windy City. The Chicago Bears host the Oakland Raiders this weekend with very little expectations.

Marshawn Lynch

Marshawn Lynch is currently listed as "questionable" with a hamstring injury. There's a 50 percent chance he will play against the 0-3 Detroit Lions on Monday Night Football. Lynch only had five carries last week against the Bears, but Thomas Rawls had 104 rushing yards in his place.

Follow Damon Salvadore on Twitter @DamonSalvadore1