Kansas City Chiefs cornerback Phillip Gaines tore his ACL, and he will miss the rest of the 2015 season, according to NFL reporter Ian Rapoport.

Gaines was a third round draft pick by Kansas City in 2014. He had six tackles this season and was injured early in a loss to the Packers Monday night. Gaines was originally thought to have a knee sprain, according to Jeol Thorman of Arrowheadpride.com.

Without Gaines, the Chiefs were forced to play Tyvon Branch at nickel, and Packers quarterback Aaron Rodgers took advantage of it, tearing their pass defense apart with five touchdowns. The good news for the Chiefs is that Sean Smith's suspension ends this week, and he can play this weekend against the Cincinnati Bengals.

Last season, Smith had 50 combined tackles and an interception. After six seasons in the NFL, Smith has recorded eight interceptions, and Kansas City will need him to be a ball hawk. The Kansas City Chiefs are ranked 28th in terms of passing yards allowed per game, and they will likely need to improve their pass defense if they want a shot in the AFC West.

Everyone in the AFC West is trailing the undefeated Denver Broncos, and pass defense will likely be crucial in this division. Without Gaines for the rest of the season, head coach Andy Reid will likely need Smith to step up.