"To be honest, I didn't hit it that good. It barely got over the bar," Oakland's strong-legged kicker said after tying an NFL record with his monster kick as the first half expired. "I hit a 70-yarder in pregame."
The Raiders (1-0) won in Denver for the fourth straight season in coach Hue Jackson's NFL head coaching debut, and handed the Broncos (0-1) their first loss in a home opener since 2000.
John Fox lost his debut as Denver's coach, and he lost at least two playmakers in the process.
Pass-rusher Elvis Dumervil (shoulder) was relegated to situational duty for three quarters, and perennial Pro Bowl cornerback Champ Bailey injured his left hamstring making a touchdown-saving tackle of Darren McFadden, who ran 22 times for 150 yards.
"It's very disappointing because we talk about having to stop Darren McFadden, and we don't do everything to stop him," said Bailey, who will go for an MRI Tuesday.
Without a ground game themselves, the Broncos went to the air and cut the deficit to 23-20 with just under four minutes left on Kyle Orton's short TD toss to Lance Ball with both his top target, Brandon Lloyd (groin), and top tailback, Knowshon Moreno (hamstring) on the sideline.
The Raiders, who ran for 190 yards, salted away the win by controlling the clock and were able to line up in victory formation after Michael Bush's 12-yard run to midfield for the first down at the 2-minute warning.
Other than his late TD throw, Orton had a tough night. He completed 24 of 46 passes for 304 yards with an interception. As he left the field, fans were chanting, "Tebow! Tebow!" for second-year quarterback Tim Tebow, who had an awful camp and is probably the No. 3 quarterback behind Brady Quinn.
"There's no consolation for close but we're still optimistic," Fox said. "We just happen to be 0-1 like half the teams in our football league."
After a first half filled with fouls, fists and frustration, the Raiders took a 16-3 lead into the locker room in wild celebration as Janikowski's 63-yard field goal fluttered over the crossbar as time expired.
That tied the mark set by Tom Dempsey in 1970 and matched by Denver's Jason Elam in 1998 at the old Mile High Stadium.
"I wanted to be 10 years in the league, break the record or tie the record and I want to win a Super Bowl," Janikowski said. "Those are my three goals. I've got two out of three."
Janikowski's teammate, punter Shane Lechler, would add a 77-yard punt in the fourth quarter.
"It's phenomenal, both of them," Jackson said. "What Sebastian did was unheard of. I think we have two of the best kickers in the league. I trust those guys, believe in them. What a kick. Obviously, a lot of people think that was the difference in the game."
Lechler's punt bounced into the end zone for a touchback, and that's just what Jackson wanted out of his punter after watching Eric Decker return his previous punt 90 yards for a touchdown. It was the eighth TD on a punt or kickoff return on opening weekend, the most in a single week in NFL history.
The Broncos kept faltering deep in Oakland territory, none more painful than when they reached the Raiders 24 and Orton had tight end Daniel Fells open going into the end zone. Only, the ball slipped out of his hand and defensive end Lamarr Houston pounced on it.
"I just feel sick about the ball slipping out of my hands like that," Orton said. "It's just one of those deals that's sickening to have happen to you. It never really happened to me before."
The Raiders, who committed 15 penalties for 131 yards, quickly capitalized, covering 65 yards in just three plays for the decisive touchdown.
Darrius Heyward-Bey caught a 17-yard pass and McFadden reeled off a 47-yard run before being dragged down just shy of the goal line by Bailey, who left the game.
Campbell took it in from there on the next snap to give the Raiders a 23-13 lead with 12:33 remaining.
Pass-rusher Von Miller, the second overall pick in the draft, speared the football out of Jacoby Ford's arms on his first snap as a pro and fellow rookie Rahim Moore, a strong safety, scooped it up at the Raiders 15. But the Broncos had to settle for Prater's 28-yard field goal.
Darryl Blackstock's block of Britton Colquitt's punt led to a 3-yard TD toss from Campbell to Marcel Reece, who trotted into the end zone after Moore failed to follow the fullback into the flat, giving Oakland a 7-3 lead it would never give up.
Moreno fumbled two snaps later, and Janikowski split the uprights through a driving rain from 37 yards out for a 10-3 lead. He added a chip shot from 21 yards out before his record-tying 63-yarder.
Colquitt's next punt traveled 65 yards and was downed at the 1, but the Broncos couldn't turn loose their "Doom and Gloom" pass-rush because Dumervil, in his first game in 21 months, jammed a shoulder in the first quarter and was used only sparingly afterward, replacing Jason Hunter on some passing downs.
Dumervil missed last season with a torn chest muscle after leading the league with 17 sacks in 2009. He moved back to defensive end from outside linebacker this summer and packed on extra muscle, making him more stout against the run with his long arms and built-in leverage.
But he was relegated to watching helplessly from the sideline as McFadden ran roughshod over the Broncos yet again.
The Raiders walloped the Broncos 59-14 in their last visit to Denver, on Oct. 24. The Broncos didn't dwell on the debacle during the week as Fox declared, "This year is 2011. Last year was 2010."
With Denver making so many mistakes, however, the result was the same.
"They're a good football team," Bailey said, "but we do so many things to help them win these games."
The Broncos started four rookies in a season opener -- Miller, Moore, TE Julius Thomas and RT Orlando Franklin -- for the first time ever. ... Lechler's 77-yard punt tied a team record set by Wayne Crow in 1961.