Bengals offensive coordinator Hue Jackson says he'll still be aggressive while waiting for Andy Dalton to return.

The last time the Bengals played in San Francisco, eight years ago Tuesday, by the way, 49ers quarterback Shaun Hill beat them in his first NFL start, 20-13.

Bengals head coach Marvin Lewis would like to return the favor this Sunday (4:25 p.m.) when they return with AJ McCarron making his first pro start because Andy Dalton misses the first gate of his 77-game career with a fractured right thumb.

Dalton was told Monday he doesn't need surgery, so the speculation begins at four weeks and no one knows if that means three or five or if he'll be back in time for the playoffs. There are three weeks left in the regular season. The playoffs begin in four weeks. Lewis called it a best-case scenario, but he also avoided the will-he-be-ready-for-the-playoffs question with "We haven't made them yet."

Which means they are saddling up McCarron to perhaps finish out the regular season. And it is hard to find a more important game in Bengals history started by a backup quarterback than this Sunday. A win puts the Bengals in the playoffs for a fifth straight season. A win coupled with a Pittsburgh loss to Denver gives the Bengals the AFC North.

Offensive coordinator Hue Jackson, taking a break Monday from crafting McCarron's first game plan, put the benediction on the stretch run.

"Hopefully we'll be able to get Andy back at some point and we'll move forward," Jackson said. "But right now it's AJ McCarron's show and he'll go lead the parade."

And now is as good as time as any to get the 800-pound Tom Brady float out of the way. After Sunday's game, McCarron happened to mention innocuously that Patriots quarterback Tom Brady got his start inheriting a playoff team. And that was the only similarity he was raising.

"I wasn't comparing myself to one of the greats of all-time. Whoever took that out is ridiculous," McCarron said in a Monday follow-up session.  "What I'm saying is Tom Brady was in the same team situation when (Drew) Bledsoe went out. We have a great team, he had a great team. That's what I put forth on that talking about what he made of his opportunity. But I feel like the big games I've played in, I played in a lot in college. It's a different game at this level but still big pressure moments and I feel like I've had a lot of those." 

 The similarities are a tad striking. Both were second-year players taken late in the draft when injuries beckoned,  McCarron in the fifth round in 2014 and Brady in the sixth round 14 years earlier. Both come out of football factories used to the pressure of rabid fan bases, McCarron in Tuscaloosa, Ala., and Brady in Ann Arbor, Mich. Both were tabbed as gym-rat guys whose intangibles were probably more of a draw than their physical skills.

The biggest difference is that Brady started 14 games that season while McCarron gets the ride at the end. But even though he's getting on late, Jackson says he's not going to protect him by anointing him a game manager.

"If you guys think he's going to turn around and hand it off 70 times to win a game, then you guys are mistaken. That's not going to happen," Jackson said. "That's not going to happen. That's not...going....to happen.

"There's a guy named A.J. Green and Marvin Jones and Tyler Eifert. We have too many good football players. So I'm not going to stymie our guys because of one position. Because I don't think we need to. This guy can play. Please. This guy can play. It's be different if we had a guy I thought couldn't play. Maybe the conversation we'd have would be different. I believe this guy can play."

Jackson concedes last Sunday against the Steelers was difficult because the game plan had been tailored to Dalton and McCarron didn't take any reps in practice. And he still had him pass 32 times in a little more than three quarters and he says if that's what it takes against the 49ers, he says McCarron can do it.

"You can't take one guy and make it just him. It's got to fit for everybody," Jackson said. "And he has a skill set that will allow it to fit for everybody. So I'm not concerned with that. I'm not concerned with what we're going to do with him."

No missed snaps. No illegal procedures. No delay of games. Jackson liked the way McCarron took control Sunday.

That is, though, the big question. What does a McCarron game plan look like as opposed to a Dalton game plan?

"It's going to be somewhat different, but not too much," Jackson said. "He's run our system. It's just a matter of locking down things with the staff about what we want to do with him and what I think is best. But it's going to come from what we do. We're not going to invent anything new."

The biggest casualty would appear to be Jackson's multiple formations that Dalton deploys so effortlessly because of his five seasons of experience. Even Jackson allowed Monday that Dalton has become an extension of him and that McCarron needs to have less on his plate.

"As much as we can. Andy was a veteran player who I had a lot of confidence in, who I didn't have to do everything for. Because the system has been his," Jackson said. "We've maybe re-organized things, but he's always hit the ground running. So far AJ has to, but now he's going to be the starter, so we'll do a few things differently with him."

But Jackson says that doesn't mean less is less. You'll still see the creativity foaming at the mouth. You won't have to say good-bye to tackles split wide and Mohamed Sanu reverses.

"We aren't going to stop being who we are. It's next man up here," Jackson said. "You guys know how I am. It's next man up. He's the next man up. So he'll go play well. We'll do whatever we have to do. You might see a formation you've never seen this week. You never know . . . We're going to make some magic happen. That's all. We will."

But it's hard to see them giving McCarron the freedom at the line that Dalton earned through the trial and error of 77 starts and 50 wins.

"Obviously everything we did with Andy -- a la the things at the line of scrimmage -- maybe will be different," Jackson said. "That's OK. That's nothing new. I want him to be as comfortable as he can be and play as well as he can play. So whatever it is that we need to do for that to happen is what we'll do."

McCarron gets that, but he says he won't exactly be a geranium when he comes to the line.  In fact, he says he doesn't see much difference, except that he'll need help from veterans like left tackle Andrew Whitworth.

"In the last game we kept with the same game plan. We didn't try to do anything basic, but stay to our same ideas," McCarron said. "Whit said it best today, everybody else is going to have to step up another level. He said nothing against me but AD has been in this offense for five years.

"There's going to be times when he can tell people certain things at the line, what to do. I think it will be the same thing. It's my job to get us in the right protection and see the things coming."

Physically, Dalton is a better runner than McCarron, although they didn't shy away from the zone read when the change was made. In fact, the pick-six came off a zone read that McCarron said he should have handed off. But McCarron also had a knack in college for extending plays out of the pocket.

"He's ready to assume any role we ask him to play within our offense," Jackson said. "I don't have any reservations or limitations with him. There are things I will get to know more about him, because he's different. He's not a backup quarterback, he's the starting quarterback for this week. Obviously there are different things that he'll feel and different things that I'll spend more time with him that way. But I have a good feel for him."

Jackson says the biggest difference between last Sunday and this Sunday is going to be practice. He feels that once McCarron gets three days with his receivers and his plays and all the reps, things will be much smoother and McCarron agreed.

"Not having one rep last week was different," McCarron said. "Being thrown into a game like that not just running out the clock like Cleveland. It will be huge getting timing with my guys. Last week (in practice) my receivers were (Brandon) Tate, Ced Peerman and James Wilder. Those guys are running backs playing receiver. It's just different getting all the chemistry back and taking a step forward. It's fun."

The biggest take away from, Monday is the confidence that both Jackson and McCarron are exuding. And, you have to remember, this isn't exactly Jackson's first rodeo. It is a hard situation. But not his hardest. This is Candyland if you go back to when he was the offensive coordinator in Atlanta in 2007, that year Shaun Hill beat the Bengals.

Jackson's starting quarterback had literally gone to the dogs in Michel Vick, late in the year head coach Bobby Petrino quit, and Jackson won a game with Chris Redman. If it's any tougher than that, they give you a medal. Then four years later when he was the head coach in Oakland and in the play-off hunt, starting quarterback Jason Campbell broke his collarbone in mid-season and Jackson ended up trading for a guy that had been on the couch all year. Carson Palmer. And they came within five minutes of making the postseason.

It's not easy out there.

"I'll take this one," Jackson said with a laugh about this backup scenario. "I'll take this one because of the backup I've got."

But he won't play McCarron like a backup. Not after what he saw Sunday.

"It's not like he was throwing dink balls, he was throwing the ball down the field. So he knows he can do that now," Jackson said. "It was a huge boost for him. It was a boost for his teammates to see him do that. So there's nobody walking around here concerned or worried about where we're going. Everybody knows where we're going. Nothing's changed. We're chasing the same goals, the same dreams. We've just got a little different leader right now and that's OK."