49ers coach Jim Harbaugh welcomes son in Week 1

SANTA CLARA — Jim Harbaugh's newborn son arrived 10 days early and just in time for Week 1 of the NFL season. And dad didn't even have to miss a full practice, just an afternoon walk-through.

Jack Jr., named after the reigning NFL Coach of the Year's father, was born Tuesday afternoon. The 8-pound, 8-ounce boy is the third child for Harbaugh and wife Sarah, joining two big sisters — and doctors said he might have been a 10-pounder if born at full-term. Though Harbaugh said Sarah had been set to be induced Thursday so he could be there.

"Everything's scary good," Harbaugh said to open his Wednesday news conference. "Jack Jr. reported for duty yesterday at 1:27 p.m. He was 8 pounds, 8 ounces. He came 10 days early, which is to be expected. The good ones like to come in early. I also think it bodes well for the 49ers. I think it's a sign of good luck to come, perhaps, Jack Jr. being born on the fourth day of the ninth month of this year."

Harbaugh, now a proud father of six kids in all, called it a "gold medal for timing" by his wife and son. The defending NFC West champion 49ers play their season opener Sunday at Green Bay.

There was plenty of work to be done, even with a new baby.

"Jack Jr. will understand in 20 years. He wants to win, too," Harbaugh said. "And my wife would understand, too. She wants us to win, too. They would understand, but it was great to be there for it."

When asked whether defensive coordinator Vic Fangio would fill in for him in the event of an emergency or necessary absence, Harbaugh gave a quick "no."

"Wild horses couldn't have dragged us away from this game coming up this Sunday," he said. "Irrelevant, hypothetical."

The 48-year-old Harbaugh, a 15-year NFL quarterback himself, isn't ready to peg his baby for a certain position — though he had a little bit of fun thinking about all the possibilities for the boy's future in uniform and on the football field.

"He could be a left tackle. He could be a linebacker, we'll see," the coach said. "I hope he'll be a linebacker and fullback, a two-way player."