Dawson kicked a 57-yard field goal with 1 second left and the Arizona Cardinals beat Jacksonville 27-24 on Sunday, snapping the Jaguars' four-game winning streak and dropping them into a first-place tie with Tennessee in the AFC South.
It was the longest field goal of the 42-year-old kicker's career and came in a maddeningly inconsistent season with six misses.
"I make it a habit not to evaluate a season in its entirety until it's over," Dawson said. "But today was sweet for our team."
It also lifted Gabbert to a win against the franchise that had given up on the quarterback.
"It's great, I love it," guard Alex Boone said of Gabbert's victory. "It's like revenge all over. It's so awesome. That (Jacksonville) is a good team out there. They are playing well and getting this win is what we needed."
The Jaguars traded up six places to draft Gabbert 10th overall in 2011, but they got rid of him after three seasons, sending him to San Francisco for a sixth-round draft pick. Gabbert signed with Arizona in the offseason as the No. 3 quarterback, and then got a chance to play when Carson Palmer and Drew Stanton got hurt.
Gabbert was 22 of 38 for 241 yards, two touchdowns and one interception while improving to 10-31 as an NFL starter.
Dawson also was good from 34, 42 and 48 yards as the Cardinals (5-6) beat a team with a winning record for the first time this season.
Jacksonville (7-4) trailed most of the game, but took a 17-16 lead when ex-Cardinal Calais Campbell returned Gabbert's fumble 10 yards for a touchdown with 12:10 to play.
"I just knew we had the game locked up," Campbell said, "but at the end of the day, they made a few big-time plays. ... I felt like I didn't play my best game today."
The Cardinals got the ball back on a punt with 16 seconds to play at their 39.
Gabbert threw two sideline completions, the second one to D.J. Foster with 6 seconds to go - Foster made a lunging tippy-toe catch that had to be reviewed - to get close enough for the winning field goal.
Coach Doug Marrone blamed himself for giving Arizona that final chance.
"If I had to do it all over again, I just would have ran the clock out and went to overtime," he said. "That is my fault."
Bortles also had a 1-yard TD run in the third quarter. He was 19 of 33 for 160 yards and an interception.
The Cardinals took the lead with a short drive on their first possession. Gabbert completed 4 of 5 for 43 yards to set up Dawson's 34-yarder.
Jacksonville finally got on the board on Josh Lambo's 43-yard field goal with 15 seconds left in the half.
Jacksonville entered as the No. 1 rushing team in the NFL at 160 yards per game, but managed a season-low 91 against the Cardinals.
Leonard Fournette carried 12 times for 25 yards. Bortles was the team's leading rusher with 62 yards on six carries.
Seals-Jones no doubt has enjoyed having Gabbert as his quarterback. Promoted from the practice squad on Sept. 25, the undrafted rookie out of Texas A&M didn't have an NFL catch until a week ago, when he caught three, two for touchdowns, from Gabbert in a loss at Houston.
Seals-Jones was back at it Sunday, catching four passes for 72 yards and a touchdown.
Already without starting offensive linemen Patrick Omameh and Jermey Parnell, the Jaguars lost linebacker Telvin Smith to a concussion in the first half. Arizona inside linebacker Deone Bucannon left in the first half with an ankle injury and Williams with a rib injury.
Jaguars: Play Indianapolis next Sunday in first of three straight home games.
Cardinals: Host NFC West-leading Los Angeles Rams next Sunday.