Both players were inactive for the 36-25 loss. Tuck missed his second straight game due to pain in his neck and a strained groin. Jacobs missed his first game this season, with what a source says is a sprained MCL.
Seattle cornerback Marcus Trufant was out with lower back spasms. He was replaced in the starting lineup by Walter Thurmond. Seattle also was without receiver Mike Williams because of a concussion. Ben Obomanu replaced him in Sunday's lineup.
Tuck said that he has contemplated sitting out until after the Giants' Week 7 bye to rest his injuries. He went through a limited practice Thursday with new equipment that included different shoulder pads and a new facemask to help alleviate the pain in his neck and guard against opposing offensive linemen pushing his head/neck area.
Coach Tom Coughlin said Tuck suffered a setback on Thursday with his groin injury and he missed Friday's practice.
Jacobs didn't practice the entire week due to swelling in his knee.
Ohm Youngmisuk covers the Giants for ESPNNewYork.com. Information from The Associated Press was used in this report.