.

ATLANTA -- Instead of micromanaging Geno Smith by making him wear a color-coded wrist band, New York Jets coach Rex Ryan came to his football senses and actually challenged his rookie quarterback to take the opposite approach Monday night.

"Let 'er rip and play with no conscience," Smith said of his coach's edict.

Smith played out of his mind, all right.

Eight days after the ugliest four-turnover performance you will ever see, Smith delivered a possible turning-point game for him and the Jets, rallying them to a dramatic, last-second upset of the Atlanta Falcons, 30-28, at the Georgia Dome.

Smith was terrific for the first 58 minutes, and he was even better in the final two, directing a seven-play, 55-yard scoring drive to set up Nick Folk's 43-yard field goal as time expired. Smith was flawless on the final drive, completing four passes to three different receivers and calling an audible -- an audible! -- on the third-down play before Folk did his thing.

If Folk had missed, it still would've been a silver-lining night for the Jets (3-2), simply because of Smith's dramatic improvement. Sure, it would've hurt, but the initial pain would've faded, replaced by the big picture -- Smith's positive strides.

That they won the game, too, beating a team that fancied itself as a Super Bowl contender, was the ultimate double-delight for the Jets, who moved to within one game of the first-place New England Patriots in the AFC East.

"We showed that we can be great," said defensive end Muhammad Wilkerson, who was just that against the Falcons (1-4).

Team success aside, this showed Smith's potential. He's not a turnover machine, after all. After 11 giveaways in the first four games, he played a clean game on a national stage.

No turnovers.

Let's repeat that: no turnovers.

"I thought he did an outstanding job for us throughout the entire game," Ryan said.

This was the kind of game the Jets envisioned when they chose Smith in the second round. That he kept his cool on the road, with ear-splitting noise, showed plenty of moxie. For a change, everybody isn't talking about his strong arm and his physical gifts. Everybody's talking about his calm under pressure.

"He's wise beyond his years," running back Mike Goodson said.

Smith didn't put up "wow" numbers, mostly because Marty Mornhinweg featured the running game, but the former West Virginia star capitalized on his chances. He completed 16 of 20 passes for 199 yards, three touchdowns and a 147.7 passer rating. And he did it without injured wide receiver Santonio Holmes and with a couple of newcomers, Goodson and wide receiver David Nelson.

More importantly, he did it in crunch time.

Thanks to a fourth-quarter defensive collapse, the Jets fell behind 28-27. Smith got the ball on the 20-yard line with 1:54 on the clock. There wasn't a rah-rah speech in the huddle.

"There was no Disney pep talk," guard Willie Colon said. "No time for that. Good offenses get it done and that's what we did."

Smith hit Stephen Hill for a 12-yard gain, Jeremy Kerley for 13 more and Hill for another 9. Smith scrambled for 8 yards and got out of bounds, stopping the clock with 37 seconds left. After a Bilal Powell run, Smith hit Clyde Gates for 3 yards.

Now it was third-and-3 from Falcons' 31, on the fringe of field-goal range. Mornhinweg sent in a pass play and put Smith in shotgun. The kid looked at the Falcons' defense and changed the play to a run, moving behind center for the snap.

"That takes [guts]," Colon said of Smith's play change.

It almost blew up, but Powell shed a tackler in the backfield and ran for 6 yards. In came Folk, who is money with the game on the line. Smith loved the moment.

"Always calm, since I was a kid," he said, describing his emotions on the final drive. "To be in that situation, to take my team down and get a field goal or touchdown. … It's great to come away with a victory."

After last week's debacle against the Tennessee Titans, Smith said he "needed to change my mentality," explaining he couldn't afford to be uptight. He would've been that way if Ryan had gone through with the ridiculous idea of slapping a remedial wrist band on him, a la Mark Sanchez, circa 2009.

Smith heeded Ryan's words -- let 'er rip. It's a fine line, playing aggressively but not recklessly, which Smith had been doing. In Tennessee, he struggled to complete two passes in a row, let alone an entire drive with no margin for error.

"He's a rookie and we made him look like a 10-year vet," Falcons safety William Moore said.

It's amazing how quickly things can change in the NFL. A week ago, a crestfallen Smith apologized to defensive teammates for all his mistakes. On this night, they were raving about him. Ryan didn't gush too much, preferring to keep it about the team.

"The key word is 'fearless,'" he said. "I challenged our team the night before to play that way, and that's exactly how we played."

Starting at quarterback -- for a change.