Breaking: Offensive line coach Alex Gibbs resigns abruptly

Seahawks offensive line coach Alex Gibbs, one of coach Pete Carroll’s key hires on his new staff, resigned from the team on Saturday, acccording to ESPN’s Adam Schefter.

Gibbs, 69, was talked out of retiring by Carroll to come to Seattle this season and is regarded as the guru of the zone-blocking scheme the Seahawks are building on this year.

The run game has struggled through the preseason, but it’s not clear yet why Gibbs stepped down just eight days before the season opener.

I’ll update with more information shortly.