The Pittsburgh Steelers are staring at their biggest game of the season. They will square off against the Kansas City Chiefs Sunday in a pivotal matchup. Pittsburgh is 7-6-1 on the season, a half game behind the Los Angeles Chargers, Indianapolis Colts and the Buffalo Bills.

The Steelers tie earlier this season against the Detroit Lions could be the difference between them making or missing the playoffs. But for that to happen, they need a victory Sunday against the Chiefs. If they are going to pull of the upset, they will have to do it without their best red zone weapon.

According to ProFootballFocus, Steelers tight end Pat Freiermuth has been ruled out for Sunday's game against the Chiefs.

Freiermuth had become one of the most reliable pass catchers for quarterback Ben Roethlisberger. He has seven receiving touchdowns this season. That leads the team. Six of those touchdowns have come over the last eight games.

In the Week 15 win over the Tennessee Titans, the Steelers tight end reeled in all four of his targets for 37 yards. But he was forced to leave the game after sustaining a concussion. It is the 2nd concussion Freiermuth has received this year.

With Roethlisberger losing a huge red zone target, head coach Mike Tomlin and offensive coordinator Matt Canada will have to find other ways to get into the end zone. Pittsburgh is likely not going to beat the Chiefs kicking field goals. 

Steelers TE Eric Ebron was already placed on injured reserve earlier this season. That leaves Zach Gentry and Kevin Rader as the only healthy tight ends on the roster. They have a combined 11 catches this season.