SANTA CLARA -- When Michael Crabtree's began his comeback from a torn Achilles, 49ers coach Jim Harbaugh wasn't expecting the wide receiver to produce the way he has entering Sunday's NFC Championship game.

"Thought that there would be a gap from where he was this year to before he got hurt," Harbaugh said Thursday.

Instead, Crabtree is seven games into his comeback, and he's produced 30 receptions for 435 yards and a touchdown.

"It's been a work in progress, and the process has been long," Crabtree said. "When I was over with (strength coach Mark Uyeyama) watching guys practice every day, playing was on my mind."

By talking up Crabtree's potential, the 49ers could be hoping to gain more running room for Frank Gore, Colin Kaepernick & Co.

Crabtree started the playoffs in vintage form, totaling eight catches for 125 yards in a wild-card win at Green Bay. That's much better than Harbaugh expected when the comeback began.

"(I was) thinking there would be some balls he wouldn't get to, some catches he wouldn't make, some tackles he wouldn't break, some separation that he wouldn't gain after coming back from a torn Achilles tendon," Harbaugh said. "But it was minor. You couldn't really even tell the difference the first couple weeks.

"To where it is now, it's as good or better. What kind of human being is able to do that? It's so rare. I can't compare it to anything I've ever seen. Very thankful that he's good and did what he did to get back and help his team."

Crabtree says he "never" thought of what hindrances he might have in his return. "At 40 years old, you're still going to have instincts."

Offensive coordinator Greg Roman said of the comeback: "I'll be honest with you, I had my doubts until I saw him pushing a sled about a month and a half ago out here. I realized it was reality."

The 49ers will need all the help they can get to win at Seattle for the first time since 2011, when Crabtree made a key catch to set up a winning field goal.

Crabtree isn't willing to endorse the Seahawks' Richard Sherman as the league's best cornerback, even though Sherman has made AP All-Pro First Team for a second straight year.

"I don't think so," Crabtree said. "I know nothing about 'Best in the league.' I just know about teams."

Crabtree's thoughts on that Seattle secondary: "They move around, and they're pretty good. We've got good guys, too. So it's going to be a good football game."

When the 49ers lost 29-3 at Seattle n Sept. 15, Crabtree was still recovering from May 22 surgery on his right Achilles. On the second game into his comeback, Crabtree had four catches for 40 yards in a 19-17 home win over the Seahawks on Dec. 8.

How much better is the 49ers offense with Crabtree?

"I don't know an exact amount, but better — significantly," Harbaugh said.