Seahawks prove Mike Macdonald's next man up mantra has its limits in loss to Lions

Let's be real. Heading into Week 4 against the Detroit Lions, the Seattle Seahawks were looking at a tough time. First off, Detroit is a good team. Secondly, Seattle was missing five starters on defense and lost another during the game.

That should not make a huge difference, however. NFL teams only have 53 players and all of them are professionals with jobs to do. If they are a second-string player and the first-string guy gets hurt, the guy who is next up needs to perform like he is a full-time starter. This is the philosophy of many football coaches, but especially one Mike Macdonald believes in.

Against Detroit, that mantra proved to be false. The players replacing Leonard Williams, Boye Mafe, Uchenna Nwosu, Jerome Baker, and Byron Murphy II did not do their jobs well. Detroit scored 42 points, had nearly 400 total yards, and quarterback Jared Goff did not throw an incompletion. Detroit also ran over and through Seattle's run defense.

Seahawks lose to the Lions as defensive backups fail

Week 4 might not have taught us anything about the team, though. Through the first three games, Seattle's defense looked much better than in previous seasons. That could still be true, but the quality of quarterbacks and offenses that Seattle played in those games was not good.

The Lions are quite good and capable of making a run at the Super Bowl this year. Still, the Seahawks' defense they faced on Monday was extremely diminished and they took advantage of that. Losing even Williams and Mafe would have been bad enough, but missing Baker and Murphy crippled Seattle's ability to stop the run.

Macdonald will always believe in the next man up, and he should. Again, the players on the team are there to do a job well. Against Detroit, they did not. The Lions schemed well, of course, but the design was used against players such as Johnathan Hankins and Trevis Gipson. At times, they have been solid players. They aren't Williams and Mafe, however.

Seattle next plays the struggling New York Giants. If Seattle gets some defensive starters back, they should be able to shut down New York. If they don't, all bets are off because the Seahawks' next men up simply are not good enough.