SEATTLE Ian Williams' first NFL start Sunday ended quickly when the 49ers' nose tackle suffered a broken left ankle on the 49ers' second defensive series, according to a league source.
Seattle center Max Unger appeared to be engaged with Williams when guard J.R. Sweezy rolled onto Williams' lower leg during a 2-yard run by Marshawn Lynch. That would technically be an illegal chop block, although no penalty was called.
Williams had to be helped to his feet and was limping badly as he was helped into the locker room for X-rays. The 49ers can't place Williams on the injured reserve/designated for return list which would allow Williams to come back late in the season because that designation already was given to linebacker Nick Moody, who broke his hand last week.
During the offseason, Williams beat out free-agent acquisition Glenn Dorsey for the starting role at nose tackle. However, those players rotated at the position during the preseason, and the plan Sunday was to give Dorsey a fair number of repetitions at nose tackle. Both played last week against the Packers, though their snaps came mainly at defensive end.
During the offseason, the 49ers had a third nose tackle, Lamar Divens, on the roster. Divens, however, was waived/injured to reduce the roster to 53 players before the regular season began. It's unclear when Divens could rejoin the team.
Williams went undrafted out of Notre Dame in 2011. Williams appeared in four games over the last two seasons; Sunday was his first start.
Lightning strikes twice At 6:02 p.m., a lightning bolt flashed across the sky outside CenturyLink Field as Seattle quarterback Russell Wilson scrambled on third down. Three minutes later, the officials halted the game and sent the teams to their locker rooms with the game scoreless. Play resumed an hour later.
"Both teams had (the delay)," receiver Kyle Williams said. "So I don't think it gave either team an advantage."
The NFL's opening game in Denver between the Broncos and Ravens was suspended for more than a half hour because of thunderstorms in the area, and Sunday's Buccaneers-Saints game went through a 69-minute delay in the first quarter.
A 2006 game between the 49ers and Seahawks in Seattle was delayed 12 minutes due to a heavy storm that produced puddles on the artificial field and momentarily knocked out power to the video screens in the stadium. The 49ers won that game 24-14.
Hard hit Jim Harbaugh, who a week ago railed against hard hits on read-option quarterbacks, watched as one of his own players delivered just a hit.
The play occurred in the second quarter when Seattle quarterback Russell Wilson hesitated before handing the ball to running back Marshawn Lynch.
Lynch gained 21 yards and Wilson was crushed by left outside linebacker Ahmad Brooks.
Before the 49ers played the Packers, Harbaugh argued that read-option quarterbacks, while still in the pocket, should enjoy the protection they receive in traditional formations. He called the league's rule on the matter "flawed and biased."
San Francisco defensive coordinator Vic Fangio said he had no issues with the rule. Neither did Seahawks coach Pete Carroll.
"I think that quarterbacks, when they're runners, they're able to get hit," Carroll said last week. "And when they're not, they're not."
Et cetera Seahawks offensive tackle Russell Okung left the game in the second quarter with an apparent foot/toe injury. Shortly after, Aldon Smith beat Okung's replacement, Paul McQuistan, for the first of his two sacks on the evening.
Before Sunday's game, the Seahawks signed defensive lineman Clinton McDonald. To make room on their roster, they released offensive tackle Mike Person, who was a seventh-round pick by the 49ers in 2011.
The most recent game between the 49ers and Seahawks was played on Jim Harbaugh's birthday. Sunday's rematch was on Pete Carroll's 62nd birthday.
The Seahawks coach was born in San Francisco and went to high school in Larkspur.
Read Matthew Barrows' blogs at www.sacbee.com/sf49ers and listen for his reports Tuesdays on ESPN Radio 1320.