Carson Palmer out with concussion vs 49ers on Thursday Night Football

Oct 2, 2016; Glendale, AZ, USA; Arizona Cardinals head coach Bruce Arians (L) watches as quarterback Carson Palmer (3) warm up prior to the game against the Los Angeles Rams at University of Phoenix Stadium. Mandatory Credit: Matt Kartozian-USA TODAY Sports
Oct 2, 2016; Glendale, AZ, USA; Arizona Cardinals head coach Bruce Arians (L) watches as quarterback Carson Palmer (3) warm up prior to the game against the Los Angeles Rams at University of Phoenix Stadium. Mandatory Credit: Matt Kartozian-USA TODAY Sports

Arizona Cardinals starting quarterback Carson Palmer isn’t traveling with the team in Week 5. Drew Stanton gets the start on Thursday Night Football.

This is starting to become a nightmarish season for the 2016 Arizona Cardinals. Not only is the team 1-3 through its first four games, but its starting quarterback Carson Palmer reportedly will not travel with the team for the Cardinals’ Thursday Night Football game with San Francisco 49ers.

ESPN’s Adam Schefter reports that Drew Stanton will start at quarterback for the Cardinals, as Palmer is still in concussion protocol after suffering one in Week 4 versus the Los Angeles Rams.

It’s not a season-ending injury for Palmer, but this is terrible news for the Cardinals’ 2016 NFC Playoff hopes. Palmer is a Pro Bowl signal caller when healthy and he can make all the necessary throws in Bruce Arians’ intricate vertical passing offense.

However, Palmer is the only player on the Cardinals that can make all of those difficult timing-based throws. Stanton has not shown that he can be a competent quarterback in Arians’ system since 2013. When Palmer tore his ACL in 2014, Stanton took over and the Cardinals offense became the worst in football.

Thursday night is a must-win game for the Cardinals. Winning at San Francisco is always difficult. The 49ers aren’t a good team, but play their best ball at home. Blaine Gabbert is not a good quarterback for the 49ers, but he should be the better signal caller on the field over Stanton on Thursday night.

If the Cardinals fall to 1-4, there is almost no chance that they can catch either the Los Angeles Rams or the Seattle Seahawks in the NFC West. Los Angeles already has a head-to-head tiebreaker on the Cardinals.

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Both Los Angeles and Seattle are 3-1. Seattle will be on its bye, but the Rams can probably beat the Buffalo Bills at home in Week 5 to move to 4-1. Three games back of Los Angeles in mid-October is bad news for the NFC Playoff dreams in the Valley of the Sun.