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BUFFALO — At his press conference, Colin Kaepernick spoke in a Muhammad Ali t-shirt. He wants to be remembered through the same lens as Ali, as an athlete who fought for social justice and succeeded.

"I can't let him die in vain," the 49ers quarterback said Sunday.

Maybe Kaepernick will be remembered this way. His kneeling during the national anthem continued at New Era Field, and players around the NFL continue to follow his lead by raising a fist or taking a knee themselves. But Sunday was a cringe-worthy reminder of what Kaepernick will not be remembered for: being a quality NFL quarterback. In a 45-16 shellacking by Buffalo, Kaepernick was abysmal.

His return to the field was more belly flop than kiss of a bicep.

When asked how poorly Kaepernick played, one anonymous Bills player didn't hold back.

"Done."

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"Terrible."

"More a distraction than a contributing member of the team."

Indeed, Colin Kaepernick was every bit as broken as he was the last time we saw him play. In the blowout loss, he had more incompletions (16) than completions (13), his 53-yard touchdown was the result of a busted coverage, he missed on big plays and could've easily thrown three to five interceptions. Clearly, the 49ers have issues everywhere. But clearly, Kaepernick is a part of the problem, too.

The magic of 2012 and 2013 has all but worn off.

He's athletic. He'll dazzle with his legs occasionally. But once an indomitable force seemingly redefining the quarterback position, Kaepernick resembles a player who was benched for Blaine Gabbert. The Bills were painfully blunt afterward: They forced Kaepernick to be a quarterback and Kaepernick failed.

"We wanted to do everything we could to make him throw the ball," cornerback Stephon Gilmore said. "I mean, he's an athlete. You can't take that from him. But when it comes to passing the ball, he can't really throw. ...We took advantage of that.

"We wanted to make him beat us with his arm, and he couldn't do that."

Praise him. Rip him. There was plenty of both emotions on Sunday from the slew of red No. 7 jerseys cheering in the crowd to the booming boos when he took the field. Afterward, Kaepernick vowed "to fight that same fight" Ali once did. But beyond the kneeling, nobody should expect much out of him as a player. Every time he needed to throw the ball—still the preeminent skill at his profession—Kaepernick was no better than former Niner lost causes Jim Druckenmiller, Tim Rattay and Cody Pickett.

Where to begin?

On San Francisco's first drive, Kaepernick overthrew Torrey Smith for what should've been a backyard, pitch-and-catch 41-yard touchdown. Later in the half, he gift-wrapped a pick-six directly to linebacker Lorenzo Alexander at the line of scrimmage which Alexander promptly dropped. On a 3rd-and-9 in the second half, the Bills showed blitz, backed off, and, with all day to throw, Kaepernick sailed one over Jeremy Kerley's head.

There was the woefully underthrown ball to Smith on a post route for what could've been another touchdown.

Or take the 3rd-and-8 Kaepernick one-hopped to Kerley's ankles...or the sack-fumble in the fourth quarter (the 49ers retained possession)...or the 3rd-and-17 Kaepernick airmailed to neighboring Cheektowaga.

Or, you know, the two throws that were nearly picked off his final drive.

His accuracy remains an eyesore.

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Not too long ago, we all thought this was the quarterback driving an on-field revolution. Kaepernick torched Green Bay for 444 total yards and four touchdowns in a divisional playoff after the 2012 season and led the 49ers to the Super Bowl. The next year, he took his team to the NFC title game and inked a $114 million contract. Defensive players here were quick to note that while Kaepernick did torch NFL defenses through a pair of postseason runs, he also had the support of a defense loaded with Pro Bowlers.

Now, he doesn't. San Francisco's defense was historically putrid in Buffalo on Sunday. The Bills shredded the 49ers for 312 yards on the ground—their most in the regular season since 1992.

Nor is he surrounded with much talent at receiver.

Said Gilmore, "They didn't really have much."

In other words, he is exposed.

Linebacker Zach Brown was the one kissing a bicep on Sunday. Not Kaepernick. After a sack, Brown mocked the quarterback's old celebration.

"We knew he was going to be rusty," Brown said. "So we just had to bring the heat. Because at the end of the day, we had to make sure he pays. Get him moving and our players will get him. Our corners and DBs are better than their receivers."

Santa Clara has become a quarterback graveyard with the toiling Gabbert, Kaepernick and Christian Ponder. Even considering coach Chip Kelly's hubris, it's shocking a pro team would trot into the regular season with this trio.

Chances are, Kaepernick will keep starting, kneeling and electrifying fans in short bursts.

At one point, he somehow shrugged off Jerry Hughes in his own end zone to gain 10 yards. He ran for 66 yards in all. Linebacker Preston Brown said that playing Kaepernick is "like playing tag." Players are darting in all directions.

Yet tag doesn't last in the NFL. The quarterbacks who do last are the ones who can squeeze tight throws through tighter windows.

Brown said Kaepernick "has a great arm" and is "definitely a guy you root for" but noted that the Bills' defensive coaches stayed busy until 2 a.m. during the week, finding ways to attack him. And safety Duke Williams, Kaepernick's teammate at Nevada, said the plan was to "set up traps" in the secondary; and those traps worked.

"Also, he hasn't played in a year-and-a-half?" Gilmore said. "So we wanted to make him do something he wasn't comfortable with."

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On the other sideline, the Bills quarterback was an efficient 17-of-26 for 179 yards and touchdowns. Tyrod Taylor has shown glimpses of being more than a raw athlete, of being a quarterback who could last. When plays dissolved Sunday, he still set his feet and made wise decisions.

"Tyrod is versatile," Williams said. "He doesn't get enough credit for how good of a passer he is. Obviously when you can extend plays the way he does, it makes the offense that much better. That's what he does. He can extend plays, keep his eyes downfield and make the big throw.

"That's what separates him from a lot of quarterbacks—especially mobile quarterbacks."

As one team crumbled to 1-5, another improved to 4-2.

Meanwhile, Kaepernick's protest will continue with no end in sight. Count on more athletes joining the movement he started, too. The NBA season is around the corner, and Kaepernick has drawn a ton of support from NFL opponents week after week. After Sunday's loss, Taylor embraced him for several moments. Kaepernick then hugged one player after another, swapping jerseys with receiver Marquise Goodwin.

As for Kaepernick's NFL future? That is much more predictable.

Take it from the first team to face him this season.

"Done," one player repeated.