PHILADELPHIA -- Sunday's comeback from a 20-point deficit hung in the balance. The 49ers defense was in a steady backpedal. Then came Justin Smith, and out went the football.
Smith, a 285-pound defensive end, chased down Philadelphia Eagles speedy receiver Jeremy Maclin and forced a fumble that safety Dashon Goldson recovered at the 49ers' 31-yard line.
Once the 49ers burned off the final 2:06, they emerged with a 24-23 victory over their stunned hosts. Then it finally was time to head home from a 10-day voyage that also featured a five-day layover in Youngstown, Ohio, and another come-from-behind road victory a week earlier at Cincinnati.
"The pursuit, the hustle (Smith) showed, I mean, that's where the story is to me," 49ers coach Jim Harbaugh said. "It's not that we stayed back east for 10 days."
Aside from optimistic hopes of a 2-0 trip, this could not have been how the 49ers (3-1) scripted it during last week's unorthodox stay in Ohio, where they practiced both at Youngstown State and in the back parking lot of a Holiday Inn.
Two road wins? Both in the Eastern time zone, where the 49ers were 3-19 since 2003?
Sunday marked the 49ers' largest comeback since their last playoff victory, when the 2002 team rallied from a 38-14 deficit to topple the New York Giants 39-38 in the wild-card round. It was their biggest regular-season comeback since Oct. 20, 1996, when they rallied from a 21-0, second-quarter deficit and beat the visiting Cincinnati Bengals 28-21. The last time the 49ers won road games in consecutive weeks: 2001. They are 3-1 for the first time since 2009, when they finished 8-8 under then-coach Mike Singletary.
"The difference was the attitude and mindset, the way we play for one another and need to have each other's back," linebacker Patrick Willis said.
Running back Frank Gore didn't start because of an injured ankle, but he still ran for a season-high 127 yards and scored on a 12-yard touchdown run that tied the score at 23 with just over three minutes left. The winning point came, fittingly, on a point-after from kicker David Akers, the Eagles' all-time leading scorer whom the 49ers signed this summer after Philadelphia let him go. That put the 49ers ahead for the first time Sunday and capped a run of 21 unanswered points.
Was this Gore's biggest win in his seven seasons?
"Yes, especially playing against the 'Dream Team,' " Gore said in reference to the Eagles' nickname, as bestowed in training camp by their backup quarterback Vince Young. "Look at us, the 49ers coming back from three touchdowns on the Dream Team. We're coming. You don't think that's big?"
Justin Smith made those points stand with his fumble-forcing play, denying the Eagles (1-3) a shot at a winning field goal. Smith never saw the ball pop out as his face hit the turf.
"You stick your arm through there and hope the ball's there," Smith said. "It's a drill you work every day. It kind of becomes repetition. Like I said, you're really not trying to get the tackle. You're trying to get the ball out. And luckily enough, it was there."
The 49ers trailed 20-3 at halftime, and elusive Eagles quarterback Michael Vick had tallied 214 yards passing plus 62 yards rushing. That deficit grew to 23-3 with 91/2 minutes left in the third quarter, when the Eagles got a 33-yard field goal from rookie Alex Henery, who would become a fourth-quarter scapegoat for missing 39- and 33-yard field-goal attempts.
Then Alex Smith morphed into a perfect quarterback. He led back-to-back touchdown drives, completing 3 of 3 passes on each series and ending them with scoring strikes of 30 yards to Joshua Morgan and 9 yards to Vernon Davis.
"At halftime and even there in the third quarter, it was a different mentality," Alex Smith said in making a comparison with past seasons. "There was no finger-pointing. This is a different team, and we stayed together."
In registering his sixth career comeback from a fourth-quarter deficit, Smith was 21 of 33 for 291 yards, the fourth-highest total of his career, with two touchdown passes, no interceptions and his first lost fumble of the season.
As for his counterpart, Vick dismissed an injured right hand to run eight times for 75 yards and complete 30 of 46 passes for 416 yards and two first-half touchdowns.
But the Eagles couldn't convert 513 total yards into more points. A second-quarter drive was spoiled on a bonehead play by Ronnie Brown, who got stopped on a third-and-goal run and still attempted a backward pass that resulted in a fumble recovery by NaVorro Bowman.
Shortly thereafter, Harbaugh delivered an abrupt halftime speech, reminding his team to just play a little better.
"It was more the heart of the players," Harbaugh said. "Just down after down, they never tired mentally or had doubt. The didn't flinch, they didn't get sacred, they just kept fighting."
For more on the 49ers, see Cam Inman's Hot Read blog at blogs.mercurynews.com/49ers.