Seattle Seahawks cut Ahtyba Rubin, Trevone Boykin to trim roster to 53

The acquisition of defensive tackle Sheldon Richardson made incumbent starter Ahtyba Rubin expendable. Rich Graessle/Icon Sportswire

The Seattle Seahawks made 39 moves to trim their roster to the NFL-mandated 53 players. Here's a closer look at those final moves:

Most significant move: The release of starting defensive tackle Ahtyba Rubin, though it wasn't a complete shock. Rubin, 31, was a two-year starter for the Seahawks and an anchor of their early-down run defense after signing with the team in free agency in 2015. He was only one year into a three-year, $12 million deal that he signed in March 2016, but Seattle needed to make room for Sheldon Richardson and his $8.1 million salary after trading for the defensive tackle on Friday. As good as he was for Seattle over the past two seasons, Rubin was older and more expensive than the team's other projected starting defensive tackle, Jarran Reed, a 2016 second-round pick. The promise that rookie third-rounder Nazair Jones has shown this summer was likely another factor in Seattle's decision to release Rubin, which saves the team $2.2 million in 2017 salary-cap space.

Trader John. Seahawks general manager John Schneider made two more trades on Saturday, giving him five over the past two days. The Seahawks sent defensive end Cassius Marsh to New England for a fifth- and a seventh-round pick, which is a strong return for a backup who had only one year of club control remaining. That seventh-rounder was the one Seattle gave New England on Thursday in the trade for cornerback Justin Coleman, who might back up Jeremy Lane in the slot. So one way to view those two trades is that Seattle got Coleman and a fifth-round pick in exchange for Marsh. The Seahawks also acquired offensive lineman Isaiah Battle in a trade with the Chiefs on Saturday, giving up a seventh-round pick. The other two trades from Friday: cornerback Tramaine Brock to Minnesota for a seventh-round pick, and Richardson from the Jets for wide receiver Jermaine Kearse and a second-round pick. The teams also swapped seventh-rounders in that trade.

A new backup QB. Second-year quarterback Trevone Boykin was among the players the Seahawks waived, which means veteran Austin Davis will back up Russell Wilson so long as Seattle doesn't find another option over the weekend. This was equal parts Boykin losing the job and Davis winning it. Boykin seemed like the favorite all summer to hold off Davis given that he was the incumbent as well as the younger and more talented of the two. But he was inconsistent in practice and threw four interceptions in the preseason, including two Thursday night. He was nearly picked off a third time in that game and also wasted a scoring chance when he mismanaged the clock in a two-minute situation before halftime. Boykin had the upside and the athleticism the Seahawks prefer in their quarterbacks, but there were only so many mistakes the team could live with. Boykin exceeded that limit. Davis, meanwhile, was much steadier. He capped off his strong preseason by throwing for the game-winning touchdown Thursday night.

Seahawks moves:

Waived (25): QB Trevone Boykin, CB Pierre Desir, WR Kasen Williams, OT Darrell Brown, LB Rodney Butler, RB Alex Collins, RB Mike Davis, WR Cyril Grayson, DT Tylor Harris, C Joey Hunt, DT Quinton Jefferson, WR Kenny Lawler, DT Jeremy Liggins, DT Greg Milhouse, WR David Moore, LB Kache Palacio, C/G Will Pericak, LB Otha Peters, WR Darreus Rogers, WR Rodney Smith, DT Garrison Smith, TE Tyrone Swoopes, OT Tyrus Thompson, CB Mike Tyson.

Terminated vested veterans (3): LB Mike Morgan, FB Marcel Reece, DT Ahtyba Rubin.

Waived/injured (3): LB Christian French, CB Demetrius McCray, DT Rodney Coe.

Injured Reserve (3): FS Marcus Cromartie, CB DeAndre Elliott, LT George Fant.

Physically Unable to Perform (1): CB DeShawn Shead.

Non-Football Injury (2): DT Malik McDowell, DE Dion Jordan.

Traded (2): CB Tramaine Brock (Minnesota), DE Cassius Marsh (New England).

Acquired via trade (1): OL Isaiah Battle (Kansas City).