At last, in Week 13, everyone got to see the dynamic tandem in San Francisco's upgraded receiving corps — and it didn't take them long to discover an impressive rhythm for a passing game in serious need of a jolt.
While the emotional Boldin helped lead the offense alongside Colin Kaepernick, Frank Gore and Vernon Davis early on, Crabtree worked through months of rehab after surgery for a torn right Achilles tendon.
"That was the vision going in, him on one side, me on the other, Vernon working the middle of the field," Boldin said. "It's tough on defenses when you have two guys outside capable of having big games, and then you have Vernon inside matched up with linebackers. So, it gives defenses fits."
Whether the Seahawks' stellar secondary can be fooled by this talented trio during the NFC championship game Sunday at Seattle will play a key factor in which of the archrivals advances to the Super Bowl.
49ers coach Jim Harbaugh wondered whether Crabtree would be the same dominant player. Even offensive coordinator Greg Roman had his doubts it would happen this season given the severity of Crabtree's injury.
"You've always got to plan for the worst-case scenario," Roman said Thursday. "Until I saw him pushing a sled about a month and a half ago out here, I realized it was reality."
Crabtree quickly returned to form as someone Harbaugh considers the best pass catcher he has seen. Crabtree might celebrate a clutch catch by pumping his arms, while Boldin tends to do so by barking at an opposing defender.
"That's just my personality. It's always been the way that I played the game," Boldin said. "I was always told if you don't play the game all out, then you're cheating yourself."
To see Crabtree back at full strength means so much for San Francisco's swagger as the team carries an eight-game winning streak into CenturyLink Field.
"You could just see at every juncture he was hitting right down the middle of the strike zone in terms of his healing. And you just watched the mental toughness, the physical toughness over that six-month period," Harbaugh said. "And then when he got back on the field, then even a, 'Wow, this is really going to be good for us.' And just thankful to him. Thankful that he went through the grueling rehab, went through the toughness, and thankful that he was good."
This is the kind of dangerous receiving unit the 49ers envisioned when Boldin came to San Francisco last March in a trade from Super Bowl champion Baltimore that sent a sixth-round draft pick to the Ravens.
Boldin noticed a difference in how Seattle's defense played the Niners in Week 2 without Crabtree to the way they did in a 19-17 49ers win Dec. 8 at Candlestick Park with him.
"Every team plays you differently as opposed to not having Crab out there," Boldin said. "He's definitely a weapon that you have to account for."
Boldin realizes, with Crabtree playing a big part, how fortunate he is to be chasing a second championship in as many years after winning it all with the Ravens against the 49ers last February.
"I'm in a situation where I'm able to possibly compete for a championship again. As a player, that's something that you cherish, that's something that you play for," Boldin said. "So, I've been blessed to be in this position."
Crabtree had eight receptions for 125 yards in a 23-20 wild-card win at Green Bay. Making his season debut on Dec. 1 against St. Louis, he played the final five games of the regular season and had 19 receptions for 284 yards and a touchdown.
"Playing was on my mind, all I wanted to do is get back on the field and do what it takes," Crabtree said. "As soon as I got hurt I asked the doctor how long it was going to take, and he told me about five months. I didn't want to tell anybody the dates, I just kept working hard."
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