SANTA CLARA, Calif. — The San Francisco 49ers fell into a black hole Sunday. Exactly what they look like if/when they resurface remains to be seen.

This much is known: When the 49ers are next visible on the football field — Sunday at the Seattle Seahawks — they will be 7-6 and in desperate need of a three-game sweep of quality teams (including San Diego and Arizona) just to have a shot at making the playoffs.

And even that might not be good enough.

Asked about this grim predicament brought on by Sunday’s 24-13 loss to the previously one-win Oakland Raiders, 49ers coach Jim Harbaugh did the predictable thing Monday.

The same thing he had done numerous times this season when confronted with an assortment of bad news ranging from suspended and injured star players, to rumors of dysfunction throughout his organization, to predictions he would either be fired or leave the team at season’s end.

He shrugged his shoulders and insisted he couldn’t wait to start piecing together a game plan to exact a measure of revenge from a Seattle that that ruined the 49ers’ Thanksgiving a week and a half ago.

“You take great love and pride in being a professional,” he insisted. “That’s every day. That’s every week. That’s every game. That’s every play until the whistle blows. You take pride in snapping on the film the next day and showing that you play with every ounce of effort that you have.”

That effort didn’t take the 49ers very far Sunday. Just one trip to the Oakland end zone, in fact.

True to his philosophy, Harbaugh didn’t point any fingers Monday. The closest he came to a criticism involved his offense and, in particular, his quarterback, Colin Kaepernick.

“It’s had a rough patch the last couple games,” he said of the offense in general. “Definitely things to improve and correct.”

Running back Frank Gore labeled the 49ers’ current standing as the lowest point of the season. Even Harbaugh seemed to acknowledge it’s dark down there.

“As my father-in-law Merle Feuerborn says, ‘It’s always darkest before the dawn,'” Harbaugh noted. “So this could be the first minutes of our finest hour. That’s the way we approach it.”

NOTES: ILB NaVorro Bowman must be placed on the 53-man active roster no later than Tuesday in order to be eligible to play this season. Bowman has not returned to team practice, but that might happen this week. Even if added to the active roster, Bowman is not likely to make his season debut Sunday at Seattle. … C Marcus Martin left Sunday’s loss in the fourth quarter because of an injured right knee. Harbaugh said Monday that preliminary reports on the extent of the injury were good. It’s not the same knee he dislocated in the preseason. … CB Chris Culliver hurt his left knee in the second quarter. He did not return to the game, but said afterward that he hadn’t re-torn the ACL that forced to miss all of last season. Harbaugh disclosed Monday that the initial report he received on the injury was encouraging. That said, Culliver’s status for this week’s game at Seattle is not known.

REPORT CARD VS. RAIDERS

PASSING OFFENSE: D-minus – Despite facing a below-average Oakland defense, Colin Kaepernick threw more interceptions (two) than touchdown passes (one) in Sunday’s 24-13 loss to the Raiders. He passed for only 174 yards and once again failed to get tight end Vernon Davis significantly involved. Davis was limited to two catches for 26 yards.

RUSHING OFFENSE: D-plus – The 49ers were so desperate for a running game Sunday, they even allowed Kaepernick to carry the ball three times. He had some success (26 yards). Just not enough of it. The same goes for Frank Gore (12 carries, 63 yards). Two more injuries — center Marcus Martin (knee) and guard Mike Iupati (ankle) — on the offensive line surely didn’t help.

PASSING DEFENSE: F – Outside linebacker Aldon Smith was a total nonfactor as a push rusher. Not that he was the only one. And injury-replacement inside linebackers Michael Wilhoite and Chris Borland demonstrated why they were backups in the first place the way they kept allowing Raiders tight end Mychal Rivera to get behind them for big-time gains.

RUSHING DEFENSE: B – A week ago, Raiders fans considered Latavius Murray the second coming of Bo Jackson. Now, after having seen the 49ers limit Murray to 76 yards on 23 carries, these same people find themselves watching a lot of college football, hoping their back of the future is available to the Raiders in next year’s draft. Yes, the 49ers’ run defense — even without two of the best inside linebackers in the league and its top two nose tackles — can have that kind of impact on an opponent’s psyche.

SPECIAL TEAMS: C-plus – Return man Bruce Ellington was one of the 49ers’ most productive players Sunday in his first game since returning from an ankle injury. And punter Andy Lee once again boomed his punts for a 52.5-yard average. But with a chance to get the floundering 49ers within one point in the fourth quarter, Phil Dawson’s critical miss from 47 yards sapped any momentum the club might have needed to complete its comeback.

COACHING: F – Either Jim Harbaugh has regressed to an offensively challenged coach or he has become a complete distraction to what was once considered a Super Bowl contender. Either way, his team’s failures must be reflected in his grade.